lib/db, lib/protocol: Compact FileInfo and BlockInfo alignment (#6215 )

* lib/db, lib/protocol: Compact FileInfo and BlockInfo alignment This fixes the following two lint warnings FileInfo: struct of size 160 bytes could be of size 136 bytes BlockInfo: struct of size 48 bytes could be of size 40 bytes by reordering fields in alignment order (64 bit fields, then 32 bit fields, then 16 bit fields (if any), then small ones). The end result is a slightly less aesthetically pleasing struct field order, but since these are the objects we often juggle in bulk and keep large queues of I think it's worth it. It's a micro optimization, but a cheap one.
lib/model, lib/protocol: Use error handling to avoid panic on non-started folder (fixes #6174 ) (#6212 )
2026-01-04 20:09:14 -05:00 · 2019-12-08 13:31:26 +01:00 · 2019-12-04 10:46:55 +01:00 · 2019-12-04 07:15:00 +01:00 · 2019-12-03 21:34:32 +01:00 · 2019-12-03 08:37:43 +01:00
2815 changed files with 63509 additions and 1121675 deletions
--- a/.codecov.yml
+++ b/.codecov.yml
@@ -0,0 +1,5 @@
+coverage:
+  range: "40...100"
+
+ignore:
+  - "**.pb.go"
--- a/.github/CODEOWNERS
+++ b/.github/CODEOWNERS
@@ -0,0 +1,2 @@
+/AUTHORS    @calmh
+/*.md       @calmh
--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -11,6 +11,14 @@ requests directly to the developers. Worst case you might get a short
 "that's a bug, please report it on GitHub" response on the forum, in which
 case we thank you for your patience and following our advice. :)

+### Please use the correct issue tracker
+
+If your problem relates to a Syncthing wrapper or [sub-project](https://github.com/syncthing) such as [Syncthing for Android](https://github.com/syncthing/syncthing-android/issues), [SyncTrayzor](https://github.com/canton7/synctrayzor) or the [documentation](https://github.com/syncthing/docs/issues), please use their respective issue trackers.
+
+### Does your log mention database corruption?
+
+If your Syncthing log reports panics because of database corruption it is most likely a fault with your system's storage or memory. Affected log entries will contain lines starting with `panic: leveldb`. You will need to delete the index database to clear this, by running `syncthing -reset-database`.
+
 ### Please do post actual bug reports and feature requests.

 If your issue is a bug report, replace this boilerplate with a description
@@ -28,7 +36,7 @@ its entirety.

 ### Version Information

-Syncthing Version: v0.x.y
+Syncthing Version: v1.x.y
 OS Version: Windows 7 / Ubuntu 14.04 / ...
 Browser Version: (if applicable, for GUI issues)

--- a/.github/PULL_REQUEST_TEMPLATE.md
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -20,13 +20,8 @@ If this is a user visible change (including API and protocol changes), add a lin
 to the corresponding pull request on https://github.com/syncthing/docs or describe
 the documentation changes necessary.

-### Authorship
+## Authorship
+
+Your name and email will be added automatically to the AUTHORS file
+based on the commit metadata.

-Every author of a code contribution (Go, Javascript, HTML, CSS etc, with the
-possible exception of minor typo corrections and similar) is recorded in the
-AUTHORS and NICKS files and the in-GUI credits. If this is your first
-contribution, a maintainer will add you properly before accepting the
-contribution. You need not do so yourself or worry about the fact that the
-"authors" automated test fails. However, if your name (such as you want it
-presented in the credits) is not visible on your Github profile or in your
-commit messages, please assist by providing it here.
--- a/.github/SECURITY.md
+++ b/.github/SECURITY.md
@@ -0,0 +1,48 @@
+## Reporting a Vulnerability
+
+If you believe that you've found a Syncthing-related security vulnerability, please report it by sending email to the address security@syncthing.net. The PGP key for security@syncthing.net (B683AD7B76CAB013) below can be used to send encrypted mail or to verify responses received from that address.
+
+```
+-----BEGIN PGP PUBLIC KEY BLOCK-----
+Version: GnuPG v1
+
+mQENBFShFlIBCACsW346HYskhKhxrdZMjyU5Ntsjvg6/ogqINDPoL10/oaIP0G+t
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+3SHCYRCqbA7mwu2k4wNNvCEM0xZqFAvaDJ4avlZ5oiMT8IFHKsjC77nkhmfXaIGt
+hn10H2MFADjvJYul7vR+Ghg1wGhTGWo2u7VVj9BI+AfvnWaouFI0cx2KNWEI/Ocj
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+pccAEQEAAYkBHwQYAQIACQUCVKEWUgIbDAAKCRC2g617dsqwEzrjB/9q0T8A4XUE
+p0g6xq86jhmh4jlEedxrfXUL3R6ejFtuKMThulxEP0xiQ7xLzBhOnvyxLCsVbjp8
+0JtJTVCq44UzUiIBuVNRoYG29uXuTUL2UtI27VhjFxMzLDwZL97tbGR6lzdM/+U5
+9PC+PIvS0yz13z2t3/x3KUOnBgxZnpy9h4AdKwjrNVtnQdGDXSKlJBLb57TFcS94
+f3roZ5Gpw3AWYSmSSiZWbhks2UNzYSQ84LAKlV1NkktO+qRc/pUqr6IxMjOKc7XP
+e8u1Nst6fN3GNqZOV+jUYs/fqrJgp1TUWjNTuf22Rl0Idz7XLPJKYFh9W7T/4MbU
+M7Q8GZuww1rk
+=No/v
+-----END PGP PUBLIC KEY BLOCK-----
+```
--- a/.gitignore
+++ b/.gitignore
@@ -17,3 +17,10 @@ RELEASE
 deb
 lib/auto/gui.files.go
 snapcraft.yaml
+prime/
+snap/
+parts/
+stage/
+*.snap
+*.bz2
+/repos
--- a/.golangci.yml
+++ b/.golangci.yml
@@ -0,0 +1,25 @@
+linters-settings:
+  maligned:
+    suggest-new: true
+
+linters:
+  enable-all: true
+  disable:
+    - goimports
+    - depguard
+    - lll
+    - gochecknoinits
+    - gochecknoglobals
+    - gofmt
+    - scopelint
+    - gocyclo
+    - funlen
+    - wsl
+    - gocognit
+
+service:
+  golangci-lint-version: 1.21.x
+  prepare:
+    - rm -f go.sum # 1.12 -> 1.13 issues with QUIC-go
+    - GO111MODULE=on go mod vendor
+    - go run build.go assets
--- a/100
+++ b/100
@@ -1,41 +1,61 @@
 # This is the official list of Syncthing authors for copyright purposes.
-# The format is:
+#
+# THIS FILE IS MOSTLY AUTO GENERATED. IF YOU'VE MADE A COMMIT TO THE
+# REPOSITORY YOU WILL BE ADDED HERE AUTOMATICALLY WITHOUT THE NEED FOR
+# ANY MANUAL ACTION.
+#
+# That said, you are welcome to correct your name or add a nickname / GitHub
+# user name as appropriate. The format is:
 #
 #    Name Name Name (nickname) <email1@example.com> <email2@example.com>
 #
-# After changing this list, run "go run script/authors.go" to sort and update
-# the GUI HTML.
+# The in-GUI authors list is periodically automatically updated from the
+# contents of this file.
 #

 Aaron Bieber (qbit) <qbit@deftly.net>
-Adam Piggott (ProactiveServices) <aD@simplypeachy.co.uk> <simplypeachy@users.noreply.github.com> <ProactiveServices@users.noreply.github.com>
+Adam Piggott (ProactiveServices) <aD@simplypeachy.co.uk> <simplypeachy@users.noreply.github.com> <ProactiveServices@users.noreply.github.com> <adam@proactiveservices.co.uk>
 Adel Qalieh (adelq) <aqalieh95@gmail.com> <adelq@users.noreply.github.com>
 Alessandro G. (alessandro.g89) <alessandro.g89@gmail.com>
 Alexander Graf (alex2108) <register-github@alex-graf.de>
 Alexandre Viau (aviau) <alexandre@alexandreviau.net> <aviau@debian.org>
 Anderson Mesquita (andersonvom) <andersonvom@gmail.com>
+andresvia <andres.via@gmail.com>
 Andrew Dunham (andrew-d) <andrew@du.nham.ca>
-Andrey D (scienmind) <scintertech@cryptolab.net>
+Andrew Rabert (nvllsvm) <ar@nullsum.net> <6550543+nvllsvm@users.noreply.github.com>
+Andrey D (scienmind) <scintertech@cryptolab.net> <scienmind@users.noreply.github.com>
+André Colomb (acolomb) <src@andre.colomb.de> <github.com@andre.colomb.de>
+andyleap <andyleap@gmail.com>
 Antoine Lamielle (0x010C) <antoine.lamielle@0x010c.fr> <gh@0x010c.fr>
 Antony Male (canton7) <antony.male@gmail.com>
+Aranjedeath <Aranjedeath@users.noreply.github.com>
 Arthur Axel fREW Schmidt (frioux) <frew@afoolishmanifesto.com> <frioux@gmail.com>
-Audrius Butkevicius (AudriusButkevicius) <audrius.butkevicius@gmail.com>
+Audrius Butkevicius (AudriusButkevicius) <audrius.butkevicius@gmail.com> <github@audrius.rocks>
+BAHADIR YILMAZ <bahadiryilmaz32@gmail.com>
 Bart De Vries (mogwa1) <devriesb@gmail.com>
 Ben Curthoys (bencurthoys) <ben@bencurthoys.com>
 Ben Schulz (uok) <ueomkail@gmail.com> <uok@users.noreply.github.com>
 Ben Shepherd (benshep) <bjashepherd@gmail.com>
 Ben Sidhom (bsidhom) <bsidhom@gmail.com>
+Benedikt Heine (bebehei) <bebe@bebehei.de>
+Benedikt Morbach <benedikt.morbach@googlemail.com>
+Benno Fünfstück <benno.fuenfstueck@gmail.com>
 Benny Ng (tpng) <benny.tpng@gmail.com>
+Boris Rybalkin <ribalkin@gmail.com>
 Brandon Philips (philips) <brandon@ifup.org>
 Brendan Long (brendanlong) <self@brendanlong.com>
 Brian R. Becker (brbecker) <brbecker@gmail.com>
 Caleb Callaway (cqcallaw) <enlightened.despot@gmail.com>
-Carsten Hagemann (Moter8) <moter8@gmail.com>
-Cathryne Linenweaver (Cathryne) <cathryne.linenweaver@gmail.com> <Cathryne@users.noreply.github.com>
+Carsten Hagemann (carstenhag) <moter8@gmail.com> <carsten@chagemann.de>
+Cathryne Linenweaver (Cathryne) <cathryne.linenweaver@gmail.com> <Cathryne@users.noreply.github.com> <katrinleinweber@MAC.local>
 Cedric Staniewski (xduugu) <cedric@gmx.ca>
 Chris Howie (cdhowie) <me@chrishowie.com>
 Chris Joel (cdata) <chris@scriptolo.gy>
+Chris Tonkinson <chris@masterbran.ch>
+chucic <chucic@seznam.cz>
 Colin Kennedy (moshen) <moshen.colin@gmail.com>
+Cromefire_ <tim.l@nghorst.net>
+Dale Visser <dale.visser@live.com>
 Daniel Bergmann (brgmnn) <dan.arne.bergmann@gmail.com> <brgmnn@users.noreply.github.com>
 Daniel Harte (norgeous) <daniel@harte.me> <daniel@danielharte.co.uk> <norgeous@users.noreply.github.com>
 Daniel Martí (mvdan) <mvdan@mvdan.cc>
@@ -43,36 +63,62 @@ Darshil Chanpura (dtchanpura) <dtchanpura@gmail.com> <dcprime314@gmail.com>
 David Rimmer (dinosore) <dinosore@dbrsoftware.co.uk>
 Denis A. (dva) <denisva@gmail.com>
 Dennis Wilson (snnd) <dw@risu.io>
+dependabot-preview[bot] <dependabot-preview[bot]@users.noreply.github.com>
+dependabot[bot] <dependabot[bot]@users.noreply.github.com>
+derekriemer <derek.riemer@colorado.edu>
+desbma <desbma@users.noreply.github.com>
 Dmitry Saveliev (dsaveliev) <d.e.saveliev@gmail.com>
 Dominik Heidler (asdil12) <dominik@heidler.eu>
 Elias Jarlebring (jarlebring) <jarlebring@gmail.com>
+Elliot Huffman <thelich2@gmail.com>
 Emil Hessman (ceh) <emil@hessman.se>
 Erik Meitner (WSGCSysadmin) <e.meitner@willystreet.coop>
+Evgeny Kuznetsov <evgeny@kuznetsov.md>
 Federico Castagnini (facastagnini) <federico.castagnini@gmail.com>
 Felix Ableitner (Nutomic) <me@nutomic.com>
 Felix Unterpaintner (bigbear2nd) <bigbear2nd@gmail.com>
 Francois-Xavier Gsell (zukoo) <fxgsell@gmail.com>
 Frank Isemann (fti7) <frank@isemann.name>
+georgespatton <georgespatton@users.noreply.github.com>
 Gilli Sigurdsson (gillisig) <gilli@vx.is>
+Graham Miln (grahammiln) <graham.miln@dssw.co.uk> <graham.miln@miln.eu>
+Han Boetes <han@boetes.org>
+Harrison Jones (harrisonhjones) <harrisonhjones@users.noreply.github.com>
 Heiko Zuerker (Smiley73) <heiko@zuerker.org>
+Hugo Locurcio <hugo.locurcio@hugo.pro>
+Iain Barnett <iainspeed@gmail.com>
+Ian Johnson (anonymouse64) <ian.johnson@canonical.com> <person.uwsome@gmail.com>
+Iskander Sharipov (Alex) <quasilyte@gmail.com>
 Jaakko Hannikainen (jgke) <jgke@jgke.fi>
 Jacek Szafarkiewicz (hadogenes) <szafar@linux.pl>
 Jake Peterson (acogdev) <jake@acogdev.com>
 Jakob Borg (calmh) <jakob@nym.se> <jakob@kastelo.net>
 James Patterson (jpjp) <jamespatterson@operamail.com> <jpjp@users.noreply.github.com>
+janost <janost@tuta.io>
 Jaroslav Malec (dzarda) <dzardacz@gmail.com>
+jaseg <githubaccount@jaseg.net>
 Jaya Chithra (jayachithra) <s.k.jayachithra@gmail.com>
 Jens Diemer (jedie) <github.com@jensdiemer.de> <git@jensdiemer.de>
+Jerry Jacobs (xor-gate) <jerry.jacobs@xor-gate.org> <xor-gate@users.noreply.github.com>
 Jochen Voss (seehuhn) <voss@seehuhn.de>
+Johan Andersson <j@i19.se>
 Johan Vromans (sciurius) <jvromans@squirrel.nl>
+John Rinehart (fuzzybear3965) <johnrichardrinehart@gmail.com>
+Jonas Thelemann <e-mail@jonas-thelemann.de>
+Jonathan Cross <jcross@gmail.com>
 Jose Manuel Delicado (jmdaweb) <jmdaweb@hotmail.com> <jmdaweb@users.noreply.github.com>
+Jörg Thalheim <Mic92@users.noreply.github.com>
+Kalle Laine <pahakalle@protonmail.com>
 Karol Różycki (krozycki) <rozycki.karol@gmail.com>
+Keith Turner <kturner@apache.org>
 Kelong Cong (kc1212) <kc04bc@gmx.com> <kc1212@users.noreply.github.com>
 Ken'ichi Kamada (kamadak) <kamada@nanohz.org>
 Kevin Allen (ironmig) <kma1660@gmail.com>
 Kevin White, Jr. (kwhite17) <kevinwhite1710@gmail.com>
+klemens <ka7@github.com>
 Kurt Fitzner (Kudalufi) <kurt@va1der.ca> <kurt.fitzner@gmail.com>
 Lars K.W. Gohlke (lkwg82) <lkwg82@gmx.de>
+Laurent Arnoud <laurent@spkdev.net>
 Laurent Etiemble (letiemble) <laurent.etiemble@gmail.com> <laurent.etiemble@monobjc.net>
 Leo Arias (elopio) <yo@elopio.net>
 Liu Siyuan (liusy182) <liusy182@gmail.com> <liusy182@hotmail.com>
@@ -82,45 +128,81 @@ Majed Abdulaziz (majedev) <majed.alhajry@gmail.com>
 Marc Laporte (marclaporte) <marc@marclaporte.com> <marc@laporte.name>
 Marc Pujol (kilburn) <kilburn@la3.org>
 Marcin Dziadus (marcindziadus) <dziadus.marcin@gmail.com>
+marco-m <marco.molteni@laposte.net>
 Mark Pulford (mpx) <mark@kyne.com.au>
 Mateusz Naściszewski (mateon1) <matin1111@wp.pl>
+Matic Potočnik <hairyfotr@gmail.com>
 Matt Burke (burkemw3) <mburke@amplify.com> <burkemw3@gmail.com>
+Matt Robenolt <matt@ydekproductions.com>
+Matteo Ruina <matteo.ruina@gmail.com>
+Maurizio Tomasi <ziotom78@gmail.com>
 Max Schulze (kralo) <max.schulze@online.de> <kralo@users.noreply.github.com>
+MaximAL <almaximal@ya.ru>
+Maxime Thirouin <m@moox.io>
 Michael Jephcote (Rewt0r) <rewt0r@gmx.com> <Rewt0r@users.noreply.github.com>
 Michael Ploujnikov (plouj) <ploujj@gmail.com>
 Michael Tilli (pyfisch) <pyfisch@gmail.com>
+Mike Boone <mike@boonedocks.net>
+MikeLund <MikeLund@users.noreply.github.com>
+Mingxuan Lin <gdlmx@users.noreply.github.com>
 Nate Morrison (nrm21) <natemorrison@gmail.com>
+Nicholas Rishel (PrototypeNM1) <rishel.nick@gmail.com> <PrototypeNM1@users.noreply.github.com>
+Nico Stapelbroek <3368018+nstapelbroek@users.noreply.github.com>
+Nicolas Braud-Santoni <nicolas@braud-santoni.eu>
 Niels Peter Roest (Niller303) <nielsproest@hotmail.com> <seje.niels@hotmail.com>
+Nils Jakobi (thunderstorm99) <jakobi.nils@gmail.com>
+Nitroretro <43112364+Nitroretro@users.noreply.github.com>
+NoLooseEnds <jon.koslung@gmail.com>
+otbutz <tbutz@optitool.de>
+Oyebanji Jacob Mayowa <oyebanji05@gmail.com>
 Pascal Jungblut (pascalj) <github@pascalj.com> <mail@pascal-jungblut.com>
 Pawel Palenica (qepasa) <pawelpalenica11@gmail.com>
+Paweł Rozlach <vespian@users.noreply.github.com>
+perewa <cavalcante.ten@gmail.com>
+Peter Badida <KeyWeeUsr@users.noreply.github.com>
+Peter Dave Hello <hsu@peterdavehello.org>
 Peter Hoeg (peterhoeg) <peter@speartail.com>
+Peter Marquardt (wwwutz) <wwwutz@gmail.com> <wwwutz@googlemail.com>
+Phil Davis <phil.davis@inf.org>
 Philippe Schommers (filoozoom) <philippe@schommers.be>
 Phill Luby (pluby) <phill.luby@newredo.com>
+Pier Paolo Ramon <ramonpierre@gmail.com>
 Piotr Bejda (piobpl) <piotrb10@gmail.com>
+Pramodh KP (pramodhkp) <pramodh.p@directi.com> <1507241+pramodhkp@users.noreply.github.com>
+Richard Hartmann <RichiH@users.noreply.github.com>
 Robert Carosi (nov1n) <robert@carosi.nl>
 Roman Zaynetdinov (zaynetro) <romanznet@gmail.com>
 Ross Smith II (rasa) <ross@smithii.com>
+rubenbe <github-com-00ff86@vandamme.email>
 Ryan Sullivan (KayoticSully) <kayoticsully@gmail.com>
 Sacheendra Talluri (sacheendra) <sacheendra.t@gmail.com>
 Scott Klupfel (kluppy) <kluppy@going2blue.com>
 Sergey Mishin (ralder) <ralder@yandex.ru>
 Simon Frei (imsodin) <freisim93@gmail.com>
+Sly_tom_cat <slytomcat@mail.ru>
 Stefan Kuntz (Stefan-Code) <stefan.github@gmail.com> <Stefan.github@gmail.com>
-Stefan Tatschner (rumpelsepp) <stefan@sevenbyte.org> <rumpelsepp@sevenbyte.org>
+Stefan Tatschner (rumpelsepp) <stefan@sevenbyte.org> <rumpelsepp@sevenbyte.org> <stefan@rumpelsepp.org>
 Suhas Gundimeda (snugghash) <suhas.gundimeda@gmail.com> <snugghash@gmail.com>
 Taylor Khan (nelsonkhan) <nelsonkhan@gmail.com>
+Thomas Hipp <thomashipp@gmail.com>
 Tim Abell (timabell) <tim@timwise.co.uk>
 Tim Howes (timhowes) <timhowes@berkeley.edu>
 Tobias Nygren (tnn2) <tnn@nygren.pp.se>
 Tobias Tom (tobiastom) <t.tom@succont.de>
+Tom Jakubowski <tom@crystae.net>
 Tomas Cerveny (kozec) <kozec@kozec.com>
+Tommy Thorn <tommy-github-email@thorn.ws>
 Tully Robinson (tojrobinson) <tully@tojr.org>
 Tyler Brazier (tylerbrazier) <tyler@tylerbrazier.com>
 Unrud (Unrud) <unrud@openaliasbox.org> <Unrud@users.noreply.github.com>
 Veeti Paananen (veeti) <veeti.paananen@rojekti.fi>
 Victor Buinsky (buinsky) <vix_booja@tut.by>
 Vil Brekin (Vilbrekin) <vilbrekin@gmail.com>
+Vladimir Rusinov <vrusinov@google.com>
+wangguoliang <liangcszzu@163.com>
 William A. Kennington III (wkennington) <william@wkennington.com>
 Wulf Weich (wweich) <wweich@users.noreply.github.com> <wweich@gmx.de> <wulf@weich-kr.de>
 Xavier O. (damajor) <damajor@gmail.com>
+xjtdy888 (xjtdy888) <xjtdy888@163.com>
 Yannic A. (eipiminus1) <eipiminusone+github@gmail.com> <eipiminus1@users.noreply.github.com>
+佛跳墙 <daoquan@qq.com>
--- a/CONDUCT.md
+++ b/CONDUCT.md
@@ -1,92 +1,73 @@
-## Conduct
+# Contributor Covenant Code of Conduct

-* We are committed to providing a friendly, safe and welcoming
-  environment for all, regardless of gender, sexual orientation,
-  disability, ethnicity, religion, or similar personal characteristic.
+## Our Pledge

-* On IRC, please avoid using overtly sexual nicknames or other nicknames
-  that might detract from a friendly, safe and welcoming environment for
-  all.
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to making participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, gender identity and expression, level of experience,
+education, socio-economic status, nationality, personal appearance, race,
+religion, or sexual identity and orientation.

-* Please be kind and courteous. There's no need to be mean or rude.
+## Our Standards

-* Respect that people have differences of opinion and that every design
-  or implementation choice carries a trade-off and numerous costs. There
-  is seldom a right answer.
+Examples of behavior that contributes to creating a positive environment
+include:

-* Please keep unstructured critique to a minimum. If you have solid
-  ideas you want to experiment with, make a fork and see how it works.
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members

-* We will exclude you from interaction if you insult, demean or harass
-  anyone. That is not welcome behaviour. We interpret the term
-  "harassment" as including the definition in the <a
-  href="http://citizencodeofconduct.org/">Citizen Code of Conduct</a>;
-  if you have any lack of clarity about what might be included in that
-  concept, please read their definition. In particular, we don't
-  tolerate behavior that excludes people in socially marginalized
-  groups.
+Examples of unacceptable behavior by participants include:

-* Private harassment is also unacceptable. No matter who you are, if you
-  feel you have been or are being harassed or made uncomfortable by a
-  community member, please contact one of the channel ops or any of the
-  Syncthing core team immediately. Whether you're a regular  contributor
-  or a newcomer, we care about making this community a safe place for
-  you and we've got your back.
+* The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting

-* Likewise any spamming, trolling, flaming, baiting or other
-  attention-stealing behaviour is not welcome.
+## Our Responsibilities

-## Moderation
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.

-These are the policies for upholding our community's standards of
-conduct in our communication channels, most notably in Syncthing-related
-IRC channels and on the web forum.
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.

-1. Remarks that violate the Syncthing standards of conduct, including
-   hateful, hurtful, oppressive, or exclusionary remarks, are not
-   allowed. (Cursing is allowed, but never targeting another user, and
-   never in a hateful manner.)
+## Scope

-2. Remarks that moderators find inappropriate, whether listed in the
-   code of conduct or not, are also not allowed.
+This Code of Conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community. Examples of
+representing a project or community include using an official project e-mail
+address, posting via an official social media account, or acting as an appointed
+representative at an online or offline event. Representation of a project may be
+further defined and clarified by project maintainers.

-3. Moderators will first respond to such remarks with a warning.
+## Enforcement

-4. If the warning is unheeded, the user will be "kicked," i.e., kicked
-   out of the communication channel to cool off.
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at security@syncthing.net. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.

-5. If the user comes back and continues to make trouble, they will be
-   banned, i.e., indefinitely excluded.
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.

-6. Moderators may choose at their discretion to un-ban the user if it
-   was a first offense and they offer the offended party a genuine
-   apology.
+## Attribution

-7. If a moderator bans someone and you think it was unjustified, please
-   take it up with that moderator, or with a different moderator, **in
-   private**. Complaints about bans in-channel are not allowed.
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html

-8. Moderators are held to a higher standard than other community
-   members. If a moderator creates an inappropriate situation, they
-   should expect less leeway than others.
-
-In the Syncthing community we strive to go the extra step to look out
-for each other. Don't just aim to be technically unimpeachable, try to
-be your best self. In particular, avoid flirting with offensive or
-sensitive issues, particularly if they're off-topic; this all too
-often leads to unnecessary fights, hurt feelings, and damaged trust;
-worse, it can drive people away from the community entirely.
-
-And if someone takes issue with something you said or did, resist the
-urge to be defensive. Just stop doing what it was they complained about
-and apologize. Even if you feel you were misinterpreted or unfairly
-accused, chances are good there was something you could've communicated
-better — remember that it's your responsibility to make your fellow
-community members comfortable. Everyone wants to get along and we are
-all here first and foremost because we want to talk about cool
-technology. You will find that people will be eager to assume good
-intent and forgive as long as you earn their trust.
-
-*Adapted from the [Rust Code of Conduct](https://github.com/rust-lang/rust/wiki/Note-development-policy#conduct)*
-
-*Adapted from the [Node.js Policy on Trolling](http://blog.izs.me/post/30036893703/policy-on-trolling)*
+[homepage]: https://www.contributor-covenant.org
--- a/28
+++ b/28
@@ -0,0 +1,28 @@
+FROM golang:1.13 AS builder
+
+WORKDIR /src
+COPY . .
+
+ENV CGO_ENABLED=0
+ENV BUILD_HOST=syncthing.net
+ENV BUILD_USER=docker
+RUN rm -f syncthing && go run build.go -no-upgrade build syncthing
+
+FROM alpine
+
+EXPOSE 8384 22000 21027/udp
+
+VOLUME ["/var/syncthing"]
+
+RUN apk add --no-cache ca-certificates su-exec
+
+COPY --from=builder /src/syncthing /bin/syncthing
+COPY --from=builder /src/script/docker-entrypoint.sh /bin/entrypoint.sh
+
+ENV PUID=1000 PGID=1000 HOME=/var/syncthing
+
+HEALTHCHECK --interval=1m --timeout=10s \
+  CMD nc -z localhost 8384 || exit 1
+
+ENV STGUIADDRESS=0.0.0.0:8384
+ENTRYPOINT ["/bin/entrypoint.sh", "/bin/syncthing", "-home", "/var/syncthing/config"]
--- a/Dockerfile.stdiscosrv
+++ b/Dockerfile.stdiscosrv
@@ -0,0 +1,28 @@
+FROM golang:1.13 AS builder
+
+WORKDIR /src
+COPY . .
+
+ENV CGO_ENABLED=0
+ENV BUILD_HOST=syncthing.net
+ENV BUILD_USER=docker
+RUN rm -f stdiscosrv && go run build.go -no-upgrade build stdiscosrv
+
+FROM alpine
+
+EXPOSE 19200 8443
+
+VOLUME ["/var/stdiscosrv"]
+
+RUN apk add --no-cache ca-certificates su-exec
+
+COPY --from=builder /src/stdiscosrv /bin/stdiscosrv
+COPY --from=builder /src/script/docker-entrypoint.sh /bin/entrypoint.sh
+
+ENV PUID=1000 PGID=1000 HOME=/var/stdiscosrv
+
+HEALTHCHECK --interval=1m --timeout=10s \
+  CMD nc -z localhost 8443 || exit 1
+
+WORKDIR /var/stdiscosrv
+ENTRYPOINT ["/bin/entrypoint.sh", "/bin/stdiscosrv"]
--- a/Dockerfile.strelaysrv
+++ b/Dockerfile.strelaysrv
@@ -0,0 +1,28 @@
+FROM golang:1.13 AS builder
+
+WORKDIR /src
+COPY . .
+
+ENV CGO_ENABLED=0
+ENV BUILD_HOST=syncthing.net
+ENV BUILD_USER=docker
+RUN rm -f strelaysrv && go run build.go -no-upgrade build strelaysrv
+
+FROM alpine
+
+EXPOSE 22067 22070
+
+VOLUME ["/var/strelaysrv"]
+
+RUN apk add --no-cache ca-certificates su-exec
+
+COPY --from=builder /src/strelaysrv /bin/strelaysrv
+COPY --from=builder /src/script/docker-entrypoint.sh /bin/entrypoint.sh
+
+ENV PUID=1000 PGID=1000 HOME=/var/strelaysrv
+
+HEALTHCHECK --interval=1m --timeout=10s \
+  CMD nc -z localhost 22067 || exit 1
+
+WORKDIR /var/strelaysrv
+ENTRYPOINT ["/bin/entrypoint.sh", "/bin/strelaysrv"]
--- a/README-Docker.md
+++ b/README-Docker.md
@@ -0,0 +1,59 @@
+# Docker Container for Syncthing
+
+Use the Dockerfile in this repo, or pull the `syncthing/syncthing` image
+from Docker Hub.
+
+Use the `/var/syncthing` volume to have the synchronized files available on the
+host. You can add more folders and map them as you prefer.
+
+Note that Syncthing runs as UID 1000 and GID 1000 by default. These may be
+altered with the ``PUID`` and ``PGID`` environment variables.
+
+## Example Usage
+
+```
+$ docker pull syncthing/syncthing
+$ docker run -p 8384:8384 -p 22000:22000 \
+    -v /wherever/st-sync:/var/syncthing \
+    syncthing/syncthing:latest
+```
+
+## Discovery
+
+Note that local device discovery will not work with the above command,
+resulting in poor local transfer rates if local device addresses are not
+manually configured.
+
+To allow local discovery, the docker host network can be used instead:
+
+```
+$ docker pull syncthing/syncthing
+$ docker run --network=host \
+    -v /wherever/st-sync:/var/syncthing \
+    syncthing/syncthing:latest
+```
+
+Be aware that syncthing alone is now in control of what interfaces and ports it
+listens on. You can edit the syncthing configuration to change the defaults if
+there are conflicts.
+
+## GUI Security
+
+By default Syncthing inside the Docker image listens on 0.0.0.0:8384 to
+allow GUI connections via the Docker proxy. This is set by the
+`STGUIADDRESS` environment variable in the Dockerfile, as it differs from
+what Syncthing would otherwise use by default. This means you should set up
+authentication in the GUI, like for any other externally reachable Syncthing
+instance. If you do not require the GUI, or you use host networking, you can
+unset the `STGUIADDRESS` variable to have Syncthing fall back to listening
+on 127.0.0.1:
+
+```
+$ docker pull syncthing/syncthing
+$ docker run -e STGUIADDRESS= \
+    -v /wherever/st-sync:/var/syncthing \
+    syncthing/syncthing:latest
+```
+
+With the environment variable unset Syncthing will follow what is set in the
+configuration file / GUI settings dialog.
--- a/README.md
+++ b/README.md
@@ -2,7 +2,6 @@

 ---

-[![Latest Downloads](https://img.shields.io/badge/latest-downloads-brightgreen.svg?style=flat-square)](https://build.syncthing.net/latest/)
 [![Latest Linux & Cross Build](https://img.shields.io/teamcity/https/build.syncthing.net/s/Syncthing_BuildLinuxCross.svg?style=flat-square&label=linux+%26+cross+build)](https://build.syncthing.net/viewType.html?buildTypeId=Syncthing_BuildLinuxCross&guest=1)
 [![Latest Windows Build](https://img.shields.io/teamcity/https/build.syncthing.net/s/Syncthing_BuildWindows.svg?style=flat-square&label=windows+build)](https://build.syncthing.net/viewType.html?buildTypeId=Syncthing_BuildWindows&guest=1)
 [![Latest Mac Build](https://img.shields.io/teamcity/https/build.syncthing.net/s/Syncthing_BuildMac.svg?style=flat-square&label=mac+build)](https://build.syncthing.net/viewType.html?buildTypeId=Syncthing_BuildMac&guest=1)
@@ -63,6 +62,10 @@ There are a few examples for keeping Syncthing running in the background
 on your system in [the etc directory][3]. There are also several [GUI
 implementations][11] for Windows, Mac and Linux.

+## Docker
+
+To run Syncthing in Docker, see [the Docker README][16].
+
 ## Vote on features/bugs

 We'd like to encourage you to [vote][12] on issues that matter to you.
@@ -87,8 +90,8 @@ D26E6ED000654A3E, available from https://syncthing.net/security.html and
 most key servers.

 There is also a built in automatic upgrade mechanism (disabled in some
-distribution channels) which uses a compiled in ECDSA signature. Mac OS
-X binaries are also properly code signed.
+distribution channels) which uses a compiled in ECDSA signature. macOS
+binaries are also properly code signed.

 ## Documentation

@@ -111,4 +114,5 @@ All code is licensed under the [MPLv2 License][7].
 [13]: https://github.com/syncthing/syncthing/blob/master/GOALS.md
 [14]: assets/logo-text-128.png
 [15]: https://syncthing.net/
+[16]: https://github.com/syncthing/syncthing/blob/master/README-Docker.md

--- a/assets/logo.ico
+++ b/assets/logo.ico
--- a/build.go
+++ b/build.go
@@ -24,6 +24,7 @@ import (
 	"os"
 	"os/exec"
 	"os/user"
+	"path"
 	"path/filepath"
 	"regexp"
 	"runtime"
@@ -39,25 +40,30 @@ var (
 	goos          string
 	noupgrade     bool
 	version       string
+	goCmd         string
 	goVersion     float64
 	race          bool
 	debug         = os.Getenv("BUILDDEBUG") != ""
-	noBuildGopath bool
 	extraTags     string
 	installSuffix string
 	pkgdir        string
+	cc            string
 	debugBinary   bool
+	coverage      bool
+	timeout       = "120s"
 )

 type target struct {
 	name              string
 	debname           string
 	debdeps           []string
+	debpre            string
 	debpost           string
 	description       string
-	buildPkg          string
+	buildPkgs         []string
 	binaryName        string
 	archiveFiles      []archiveFile
+	systemdServices   []string
 	installationFiles []archiveFile
 	tags              []string
 }
@@ -71,9 +77,8 @@ type archiveFile struct {
 var targets = map[string]target{
 	"all": {
 		// Only valid for the "build" and "install" commands as it lacks all
-		// the archive creation stuff.
-		buildPkg: "github.com/syncthing/syncthing/cmd/...",
-		tags:     []string{"purego"},
+		// the archive creation stuff. buildPkgs gets filled out in init()
+		tags: []string{"purego"},
 	},
 	"syncthing": {
 		// The default target for "build", "install", "tar", "zip", "deb", etc.
@@ -82,7 +87,7 @@ var targets = map[string]target{
 		debdeps:     []string{"libc6", "procps"},
 		debpost:     "script/post-upgrade",
 		description: "Open Source Continuous File Synchronization",
-		buildPkg:    "github.com/syncthing/syncthing/cmd/syncthing",
+		buildPkgs:   []string{"github.com/syncthing/syncthing/cmd/syncthing"},
 		binaryName:  "syncthing", // .exe will be added automatically for Windows builds
 		archiveFiles: []archiveFile{
 			{src: "{{binary}}", dst: "{{binary}}", perm: 0755},
@@ -110,14 +115,23 @@ var targets = map[string]target{
 			{src: "etc/linux-systemd/system/syncthing-resume.service", dst: "deb/lib/systemd/system/syncthing-resume.service", perm: 0644},
 			{src: "etc/linux-systemd/user/syncthing.service", dst: "deb/usr/lib/systemd/user/syncthing.service", perm: 0644},
 			{src: "etc/firewall-ufw/syncthing", dst: "deb/etc/ufw/applications.d/syncthing", perm: 0644},
+			{src: "etc/linux-desktop/syncthing-start.desktop", dst: "deb/usr/share/applications/syncthing-start.desktop", perm: 0644},
+			{src: "etc/linux-desktop/syncthing-ui.desktop", dst: "deb/usr/share/applications/syncthing-ui.desktop", perm: 0644},
+			{src: "assets/logo-32.png", dst: "deb/usr/share/icons/hicolor/32x32/apps/syncthing.png", perm: 0644},
+			{src: "assets/logo-64.png", dst: "deb/usr/share/icons/hicolor/64x64/apps/syncthing.png", perm: 0644},
+			{src: "assets/logo-128.png", dst: "deb/usr/share/icons/hicolor/128x128/apps/syncthing.png", perm: 0644},
+			{src: "assets/logo-256.png", dst: "deb/usr/share/icons/hicolor/256x256/apps/syncthing.png", perm: 0644},
+			{src: "assets/logo-512.png", dst: "deb/usr/share/icons/hicolor/512x512/apps/syncthing.png", perm: 0644},
+			{src: "assets/logo-only.svg", dst: "deb/usr/share/icons/hicolor/scalable/apps/syncthing.svg", perm: 0644},
 		},
 	},
 	"stdiscosrv": {
 		name:        "stdiscosrv",
 		debname:     "syncthing-discosrv",
 		debdeps:     []string{"libc6"},
+		debpre:      "cmd/stdiscosrv/scripts/preinst",
 		description: "Syncthing Discovery Server",
-		buildPkg:    "github.com/syncthing/syncthing/cmd/stdiscosrv",
+		buildPkgs:   []string{"github.com/syncthing/syncthing/cmd/stdiscosrv"},
 		binaryName:  "stdiscosrv", // .exe will be added automatically for Windows builds
 		archiveFiles: []archiveFile{
 			{src: "{{binary}}", dst: "{{binary}}", perm: 0755},
@@ -125,12 +139,17 @@ var targets = map[string]target{
 			{src: "LICENSE", dst: "LICENSE.txt", perm: 0644},
 			{src: "AUTHORS", dst: "AUTHORS.txt", perm: 0644},
 		},
+		systemdServices: []string{
+			"cmd/stdiscosrv/etc/linux-systemd/stdiscosrv.service",
+		},
 		installationFiles: []archiveFile{
 			{src: "{{binary}}", dst: "deb/usr/bin/{{binary}}", perm: 0755},
 			{src: "cmd/stdiscosrv/README.md", dst: "deb/usr/share/doc/syncthing-discosrv/README.txt", perm: 0644},
-			{src: "cmd/stdiscosrv/LICENSE", dst: "deb/usr/share/doc/syncthing-discosrv/LICENSE.txt", perm: 0644},
+			{src: "LICENSE", dst: "deb/usr/share/doc/syncthing-discosrv/LICENSE.txt", perm: 0644},
 			{src: "AUTHORS", dst: "deb/usr/share/doc/syncthing-discosrv/AUTHORS.txt", perm: 0644},
 			{src: "man/stdiscosrv.1", dst: "deb/usr/share/man/man1/stdiscosrv.1", perm: 0644},
+			{src: "cmd/stdiscosrv/etc/linux-systemd/default", dst: "deb/etc/default/syncthing-discosrv", perm: 0644},
+			{src: "cmd/stdiscosrv/etc/firewall-ufw/stdiscosrv", dst: "deb/etc/ufw/applications.d/stdiscosrv", perm: 0644},
 		},
 		tags: []string{"purego"},
 	},
@@ -138,21 +157,29 @@ var targets = map[string]target{
 		name:        "strelaysrv",
 		debname:     "syncthing-relaysrv",
 		debdeps:     []string{"libc6"},
+		debpre:      "cmd/strelaysrv/scripts/preinst",
 		description: "Syncthing Relay Server",
-		buildPkg:    "github.com/syncthing/syncthing/cmd/strelaysrv",
+		buildPkgs:   []string{"github.com/syncthing/syncthing/cmd/strelaysrv"},
 		binaryName:  "strelaysrv", // .exe will be added automatically for Windows builds
 		archiveFiles: []archiveFile{
 			{src: "{{binary}}", dst: "{{binary}}", perm: 0755},
 			{src: "cmd/strelaysrv/README.md", dst: "README.txt", perm: 0644},
 			{src: "cmd/strelaysrv/LICENSE", dst: "LICENSE.txt", perm: 0644},
+			{src: "LICENSE", dst: "LICENSE.txt", perm: 0644},
 			{src: "AUTHORS", dst: "AUTHORS.txt", perm: 0644},
 		},
+		systemdServices: []string{
+			"cmd/strelaysrv/etc/linux-systemd/strelaysrv.service",
+		},
 		installationFiles: []archiveFile{
 			{src: "{{binary}}", dst: "deb/usr/bin/{{binary}}", perm: 0755},
 			{src: "cmd/strelaysrv/README.md", dst: "deb/usr/share/doc/syncthing-relaysrv/README.txt", perm: 0644},
 			{src: "cmd/strelaysrv/LICENSE", dst: "deb/usr/share/doc/syncthing-relaysrv/LICENSE.txt", perm: 0644},
+			{src: "LICENSE", dst: "deb/usr/share/doc/syncthing-relaysrv/LICENSE.txt", perm: 0644},
 			{src: "AUTHORS", dst: "deb/usr/share/doc/syncthing-relaysrv/AUTHORS.txt", perm: 0644},
 			{src: "man/strelaysrv.1", dst: "deb/usr/share/man/man1/strelaysrv.1", perm: 0644},
+			{src: "cmd/strelaysrv/etc/linux-systemd/default", dst: "deb/etc/default/syncthing-relaysrv", perm: 0644},
+			{src: "cmd/strelaysrv/etc/firewall-ufw/strelaysrv", dst: "deb/etc/ufw/applications.d/strelaysrv", perm: 0644},
 		},
 	},
 	"strelaypoolsrv": {
@@ -160,7 +187,7 @@ var targets = map[string]target{
 		debname:     "syncthing-relaypoolsrv",
 		debdeps:     []string{"libc6"},
 		description: "Syncthing Relay Pool Server",
-		buildPkg:    "github.com/syncthing/syncthing/cmd/strelaypoolsrv",
+		buildPkgs:   []string{"github.com/syncthing/syncthing/cmd/strelaypoolsrv"},
 		binaryName:  "strelaypoolsrv", // .exe will be added automatically for Windows builds
 		archiveFiles: []archiveFile{
 			{src: "{{binary}}", dst: "{{binary}}", perm: 0755},
@@ -177,7 +204,31 @@ var targets = map[string]target{
 	},
 }

+// These are repos we need to clone to run "go generate"
+
+type dependencyRepo struct {
+	path   string
+	repo   string
+	commit string
+}
+
+var dependencyRepos = []dependencyRepo{
+	{path: "xdr", repo: "https://github.com/calmh/xdr.git", commit: "08e072f9cb16"},
+}
+
 func init() {
+	all := targets["all"]
+	pkgs, _ := filepath.Glob("cmd/*")
+	for _, pkg := range pkgs {
+		pkg = filepath.Base(pkg)
+		if strings.HasPrefix(pkg, ".") {
+			// ignore dotfiles
+			continue
+		}
+		all.buildPkgs = append(all.buildPkgs, fmt.Sprintf("github.com/syncthing/syncthing/cmd/%s", pkg))
+	}
+	targets["all"] = all
+
 	// The "syncthing" target includes a few more files found in the "etc"
 	// and "extra" dirs.
 	syncthingPkg := targets["syncthing"]
@@ -205,41 +256,6 @@ func main() {
 		}()
 	}

-	if gopath := gopath(); gopath == "" {
-		gopath, err := temporaryBuildDir()
-		if err != nil {
-			log.Fatal(err)
-		}
-		if !noBuildGopath {
-			lazyRebuildAssets()
-			if err := buildGOPATH(gopath); err != nil {
-				log.Fatal(err)
-			}
-		}
-		os.Setenv("GOPATH", gopath)
-		log.Println("GOPATH is", gopath)
-	} else {
-		inside := false
-		wd, _ := os.Getwd()
-		wd, _ = filepath.EvalSymlinks(wd)
-		for _, p := range filepath.SplitList(gopath) {
-			p, _ = filepath.EvalSymlinks(p)
-			if filepath.Join(p, "src/github.com/syncthing/syncthing") == wd {
-				inside = true
-				break
-			}
-		}
-		if !inside {
-			fmt.Println("You seem to have GOPATH set but the Syncthing source not placed correctly within it, which may cause problems.")
-		}
-	}
-
-	// Set path to $GOPATH/bin:$PATH so that we can for sure find tools we
-	// might have installed during "build.go setup".
-	os.Setenv("PATH", fmt.Sprintf("%s%cbin%c%s", os.Getenv("GOPATH"), os.PathSeparator, os.PathListSeparator, os.Getenv("PATH")))
-
-	checkArchitecture()
-
 	// Invoking build.go with no parameters at all builds everything (incrementally),
 	// which is what you want for maximum error checking during development.
 	if flag.NArg() == 0 {
@@ -261,20 +277,8 @@ func main() {
 	}
 }

-func checkArchitecture() {
-	switch goarch {
-	case "386", "amd64", "arm", "arm64", "ppc64", "ppc64le", "mips", "mipsle":
-		break
-	default:
-		log.Printf("Unknown goarch %q; proceed with caution!", goarch)
-	}
-}
-
 func runCommand(cmd string, target target) {
 	switch cmd {
-	case "setup":
-		setup()
-
 	case "install":
 		var tags []string
 		if noupgrade {
@@ -322,9 +326,6 @@ func runCommand(cmd string, target target) {
 	case "snap":
 		buildSnap(target)

-	case "clean":
-		clean()
-
 	case "vet":
 		metalintShort()

@@ -337,13 +338,6 @@ func runCommand(cmd string, target target) {
 	case "version":
 		fmt.Println(getVersion())

-	case "gopath":
-		gopath, err := temporaryBuildDir()
-		if err != nil {
-			log.Fatal(err)
-		}
-		fmt.Println(gopath)
-
 	default:
 		log.Fatalf("Unknown command %q", cmd)
 	}
@@ -352,63 +346,41 @@ func runCommand(cmd string, target target) {
 func parseFlags() {
 	flag.StringVar(&goarch, "goarch", runtime.GOARCH, "GOARCH")
 	flag.StringVar(&goos, "goos", runtime.GOOS, "GOOS")
+	flag.StringVar(&goCmd, "gocmd", "go", "Specify `go` command")
 	flag.BoolVar(&noupgrade, "no-upgrade", noupgrade, "Disable upgrade functionality")
 	flag.StringVar(&version, "version", getVersion(), "Set compiled in version string")
 	flag.BoolVar(&race, "race", race, "Use race detector")
-	flag.BoolVar(&noBuildGopath, "no-build-gopath", noBuildGopath, "Don't build GOPATH, assume it's OK")
 	flag.StringVar(&extraTags, "tags", extraTags, "Extra tags, space separated")
 	flag.StringVar(&installSuffix, "installsuffix", installSuffix, "Install suffix, optional")
 	flag.StringVar(&pkgdir, "pkgdir", "", "Set -pkgdir parameter for `go build`")
+	flag.StringVar(&cc, "cc", os.Getenv("CC"), "Set CC environment variable for `go build`")
 	flag.BoolVar(&debugBinary, "debug-binary", debugBinary, "Create unoptimized binary to use with delve, set -gcflags='-N -l' and omit -ldflags")
+	flag.BoolVar(&coverage, "coverage", coverage, "Write coverage profile of tests to coverage.txt")
 	flag.Parse()
 }

-func setup() {
-	packages := []string{
-		"github.com/alecthomas/gometalinter",
-		"github.com/AlekSi/gocov-xml",
-		"github.com/axw/gocov/gocov",
-		"github.com/FiloSottile/gvt",
-		"github.com/golang/lint/golint",
-		"github.com/gordonklaus/ineffassign",
-		"github.com/mdempsky/unconvert",
-		"github.com/mitchellh/go-wordwrap",
-		"github.com/opennota/check/cmd/...",
-		"github.com/tsenart/deadcode",
-		"golang.org/x/net/html",
-		"golang.org/x/tools/cmd/cover",
-		"honnef.co/go/tools/cmd/gosimple",
-		"honnef.co/go/tools/cmd/staticcheck",
-		"honnef.co/go/tools/cmd/unused",
-	}
-	for _, pkg := range packages {
-		fmt.Println(pkg)
-		runPrint("go", "get", "-u", pkg)
-	}
-
-	runPrint("go", "install", "-v", "github.com/syncthing/syncthing/vendor/github.com/gogo/protobuf/protoc-gen-gogofast")
-}
-
 func test(pkgs ...string) {
 	lazyRebuildAssets()

-	useRace := runtime.GOARCH == "amd64"
-	switch runtime.GOOS {
-	case "darwin", "linux", "freebsd", "windows":
-	default:
-		useRace = false
+	args := []string{"test", "-short", "-timeout", timeout, "-tags", "purego"}
+
+	if runtime.GOARCH == "amd64" {
+		switch runtime.GOOS {
+		case "darwin", "linux", "freebsd": // , "windows": # See https://github.com/golang/go/issues/27089
+			args = append(args, "-race")
+		}
 	}

-	if useRace {
-		runPrint("go", append([]string{"test", "-short", "-race", "-timeout", "60s", "-tags", "purego"}, pkgs...)...)
-	} else {
-		runPrint("go", append([]string{"test", "-short", "-timeout", "60s", "-tags", "purego"}, pkgs...)...)
+	if coverage {
+		args = append(args, "-covermode", "atomic", "-coverprofile", "coverage.txt", "-coverpkg", strings.Join(pkgs, ","))
 	}
+
+	runPrint(goCmd, append(args, pkgs...)...)
 }

 func bench(pkgs ...string) {
 	lazyRebuildAssets()
-	runPrint("go", append([]string{"test", "-run", "NONE", "-bench", "."}, pkgs...)...)
+	runPrint(goCmd, append([]string{"test", "-run", "NONE", "-bench", "."}, pkgs...)...)
 }

 func install(target target, tags []string) {
@@ -422,30 +394,63 @@ func install(target target, tags []string) {
 	}
 	os.Setenv("GOBIN", filepath.Join(cwd, "bin"))

-	args := []string{"install", "-v"}
-	args = appendParameters(args, tags, target)
-
 	os.Setenv("GOOS", goos)
 	os.Setenv("GOARCH", goarch)
-	runPrint("go", args...)
+	os.Setenv("CC", cc)
+
+	// On Windows generate a special file which the Go compiler will
+	// automatically use when generating Windows binaries to set things like
+	// the file icon, version, etc.
+	if goos == "windows" {
+		sysoPath, err := shouldBuildSyso(cwd)
+		if err != nil {
+			log.Printf("Warning: Windows binaries will not have file information encoded: %v", err)
+		}
+		defer shouldCleanupSyso(sysoPath)
+	}
+
+	for _, pkg := range target.buildPkgs {
+		args := []string{"install", "-v"}
+		args = appendParameters(args, tags, pkg)
+
+		runPrint(goCmd, args...)
+	}
 }

 func build(target target, tags []string) {
 	lazyRebuildAssets()
-
 	tags = append(target.tags, tags...)

 	rmr(target.BinaryName())

-	args := []string{"build", "-i", "-v"}
-	args = appendParameters(args, tags, target)
-
 	os.Setenv("GOOS", goos)
 	os.Setenv("GOARCH", goarch)
-	runPrint("go", args...)
+	os.Setenv("CC", cc)
+
+	// On Windows generate a special file which the Go compiler will
+	// automatically use when generating Windows binaries to set things like
+	// the file icon, version, etc.
+	if goos == "windows" {
+		cwd, err := os.Getwd()
+		if err != nil {
+			log.Fatal(err)
+		}
+		sysoPath, err := shouldBuildSyso(cwd)
+		if err != nil {
+			log.Printf("Warning: Windows binaries will not have file information encoded: %v", err)
+		}
+		defer shouldCleanupSyso(sysoPath)
+	}
+
+	for _, pkg := range target.buildPkgs {
+		args := []string{"build", "-v"}
+		args = appendParameters(args, tags, pkg)
+
+		runPrint(goCmd, args...)
+	}
 }

-func appendParameters(args []string, tags []string, target target) []string {
+func appendParameters(args []string, tags []string, pkg string) []string {
 	if pkgdir != "" {
 		args = append(args, "-pkgdir", pkgdir)
 	}
@@ -461,7 +466,7 @@ func appendParameters(args []string, tags []string, target target) []string {

 	if !debugBinary {
 		// Regular binaries get version tagged and skip some debug symbols
-		args = append(args, "-ldflags", ldflags())
+		args = append(args, "-ldflags", ldflags(path.Base(pkg)))
 	} else {
 		// -gcflags to disable optimizations and inlining. Skip -ldflags
 		// because `Could not launch program: decoding dwarf section info at
@@ -470,7 +475,7 @@ func appendParameters(args []string, tags []string, target target) []string {
 		args = append(args, "-gcflags", "-N -l")
 	}

-	return append(args, target.buildPkg)
+	return append(args, pkg)
 }

 func buildTar(target target) {
@@ -484,10 +489,7 @@ func buildTar(target target) {
 	}

 	build(target, tags)
-
-	if goos == "darwin" {
-		macosCodesign(target.BinaryName())
-	}
+	codesign(target)

 	for i := range target.archiveFiles {
 		target.archiveFiles[i].src = strings.Replace(target.archiveFiles[i].src, "{{binary}}", target.BinaryName(), 1)
@@ -510,10 +512,7 @@ func buildZip(target target) {
 	}

 	build(target, tags)
-
-	if goos == "windows" {
-		windowsCodesign(target.BinaryName())
-	}
+	codesign(target)

 	for i := range target.archiveFiles {
 		target.archiveFiles[i].src = strings.Replace(target.archiveFiles[i].src, "{{binary}}", target.BinaryName(), 1)
@@ -577,9 +576,15 @@ func buildDeb(target target) {
 	for _, dep := range target.debdeps {
 		args = append(args, "-d", dep)
 	}
+	for _, service := range target.systemdServices {
+		args = append(args, "--deb-systemd", service)
+	}
 	if target.debpost != "" {
 		args = append(args, "--after-upgrade", target.debpost)
 	}
+	if target.debpre != "" {
+		args = append(args, "--before-install", target.debpre)
+	}
 	runPrint("fpm", args...)
 }

@@ -599,6 +604,8 @@ func buildSnap(target target) {
 	snaparch := goarch
 	if snaparch == "armhf" {
 		goarch = "arm"
+	} else if snaparch == "i386" {
+		goarch = "386"
 	}
 	snapver := version
 	if strings.HasPrefix(snapver, "v") {
@@ -609,9 +616,10 @@ func buildSnap(target target) {
 		snapgrade = "stable"
 	}
 	err = tmpl.Execute(f, map[string]string{
-		"Version":      snapver,
-		"Architecture": snaparch,
-		"Grade":        snapgrade,
+		"Version":            snapver,
+		"HostArchitecture":   runtime.GOARCH,
+		"TargetArchitecture": snaparch,
+		"Grade":              snapgrade,
 	})
 	if err != nil {
 		log.Fatal(err)
@@ -621,6 +629,56 @@ func buildSnap(target target) {
 	runPrint("snapcraft")
 }

+func shouldBuildSyso(dir string) (string, error) {
+	jsonPath := filepath.Join(dir, "versioninfo.json")
+	file, err := os.Create(filepath.Join(dir, "versioninfo.json"))
+	if err != nil {
+		return "", errors.New("failed to create " + jsonPath + ": " + err.Error())
+	}
+
+	major, minor, patch, build := semanticVersion()
+	fmt.Fprintf(file, `{
+    "FixedFileInfo": {
+        "FileVersion": {
+            "Major": %s,
+            "Minor": %s,
+            "Patch": %s,
+            "Build": %s
+        }
+    },
+    "StringFileInfo": {
+        "FileDescription": "Open Source Continuous File Synchronization",
+        "LegalCopyright": "The Syncthing Authors",
+        "ProductVersion": "%s",
+        "ProductName": "Syncthing"
+    },
+    "IconPath": "assets/logo.ico"
+}`, major, minor, patch, build, getVersion())
+	file.Close()
+	defer func() {
+		if err := os.Remove(jsonPath); err != nil {
+			log.Printf("Warning: unable to remove generated %s: %v. Please remove it manually.", jsonPath, err)
+		}
+	}()
+
+	sysoPath := filepath.Join(dir, "cmd", "syncthing", "resource.syso")
+
+	if _, err := runError("goversioninfo", "-o", sysoPath); err != nil {
+		return "", errors.New("failed to create " + sysoPath + ": " + err.Error())
+	}
+
+	return sysoPath, nil
+}
+
+func shouldCleanupSyso(sysoFilePath string) {
+	if sysoFilePath == "" {
+		return
+	}
+	if err := os.Remove(sysoFilePath); err != nil {
+		log.Printf("Warning: unable to remove generated %s: %v. Please remove it manually.", sysoFilePath, err)
+	}
+}
+
 // copyFile copies a file from src to dst, ensuring the containing directory
 // exists. The permission bits are copied as well. If dst already exists and
 // the contents are identical to src the modification time is not updated.
@@ -659,6 +717,7 @@ func listFiles(dir string) []string {
 		if err != nil {
 			return err
 		}
+
 		if fi.Mode().IsRegular() {
 			res = append(res, path)
 		}
@@ -668,12 +727,12 @@ func listFiles(dir string) []string {
 }

 func rebuildAssets() {
-	runPipe("lib/auto/gui.files.go", "go", "run", "script/genassets.go", "gui")
-	runPipe("cmd/strelaypoolsrv/auto/gui.go", "go", "run", "script/genassets.go", "cmd/strelaypoolsrv/gui")
+	os.Setenv("SOURCE_DATE_EPOCH", fmt.Sprint(buildStamp()))
+	runPrint(goCmd, "generate", "github.com/syncthing/syncthing/lib/auto", "github.com/syncthing/syncthing/cmd/strelaypoolsrv/auto")
 }

 func lazyRebuildAssets() {
-	if shouldRebuildAssets("lib/auto/gui.files.go", "gui") || shouldRebuildAssets("cmd/strelaypoolsrv/auto/gui.go", "cmd/strelaypoolsrv/auto/gui") {
+	if shouldRebuildAssets("lib/auto/gui.files.go", "gui") || shouldRebuildAssets("cmd/strelaypoolsrv/auto/gui.files.go", "cmd/strelaypoolsrv/auto/gui") {
 		rebuildAssets()
 	}
 }
@@ -705,12 +764,28 @@ func shouldRebuildAssets(target, srcdir string) bool {
 }

 func proto() {
-	runPrint("go", "generate", "github.com/syncthing/syncthing/lib/...", "github.com/syncthing/syncthing/cmd/stdiscosrv")
+	pv := protobufVersion()
+	dependencyRepos = append(dependencyRepos,
+		dependencyRepo{path: "protobuf", repo: "https://github.com/gogo/protobuf.git", commit: pv},
+	)
+
+	runPrint(goCmd, "get", fmt.Sprintf("github.com/gogo/protobuf/protoc-gen-gogofast@%v", pv))
+	os.MkdirAll("repos", 0755)
+	for _, dep := range dependencyRepos {
+		path := filepath.Join("repos", dep.path)
+		if _, err := os.Stat(path); err != nil {
+			runPrintInDir("repos", "git", "clone", dep.repo, dep.path)
+		} else {
+			runPrintInDir(path, "git", "fetch")
+		}
+		runPrintInDir(path, "git", "checkout", dep.commit)
+	}
+	runPrint(goCmd, "generate", "github.com/syncthing/syncthing/lib/...", "github.com/syncthing/syncthing/cmd/stdiscosrv")
 }

 func translate() {
 	os.Chdir("gui/default/assets/lang")
-	runPipe("lang-en-new.json", "go", "run", "../../../../script/translate.go", "lang-en.json", "../../../")
+	runPipe("lang-en-new.json", goCmd, "run", "../../../../script/translate.go", "lang-en.json", "../../../")
 	os.Remove("lang-en.json")
 	err := os.Rename("lang-en-new.json", "lang-en.json")
 	if err != nil {
@@ -721,15 +796,10 @@ func translate() {

 func transifex() {
 	os.Chdir("gui/default/assets/lang")
-	runPrint("go", "run", "../../../../script/transifexdl.go")
+	runPrint(goCmd, "run", "../../../../script/transifexdl.go")
 }

-func clean() {
-	rmr("bin")
-	rmr(filepath.Join(os.Getenv("GOPATH"), fmt.Sprintf("pkg/%s_%s/github.com/syncthing", goos, goarch)))
-}
-
-func ldflags() string {
+func ldflags(program string) string {
 	sep := '='
 	if goVersion > 0 && goVersion < 1.5 {
 		sep = ' '
@@ -737,10 +807,14 @@ func ldflags() string {

 	b := new(bytes.Buffer)
 	b.WriteString("-w")
-	fmt.Fprintf(b, " -X main.Version%c%s", sep, version)
-	fmt.Fprintf(b, " -X main.BuildStamp%c%d", sep, buildStamp())
-	fmt.Fprintf(b, " -X main.BuildUser%c%s", sep, buildUser())
-	fmt.Fprintf(b, " -X main.BuildHost%c%s", sep, buildHost())
+	fmt.Fprintf(b, " -X github.com/syncthing/syncthing/lib/build.Version%c%s", sep, version)
+	fmt.Fprintf(b, " -X github.com/syncthing/syncthing/lib/build.Stamp%c%d", sep, buildStamp())
+	fmt.Fprintf(b, " -X github.com/syncthing/syncthing/lib/build.User%c%s", sep, buildUser())
+	fmt.Fprintf(b, " -X github.com/syncthing/syncthing/lib/build.Host%c%s", sep, buildHost())
+	fmt.Fprintf(b, " -X github.com/syncthing/syncthing/lib/build.Program%c%s", sep, program)
+	if v := os.Getenv("EXTRA_LDFLAGS"); v != "" {
+		fmt.Fprintf(b, " %s", v)
+	}
 	return b.String()
 }

@@ -797,6 +871,15 @@ func getVersion() string {
 	return "unknown-dev"
 }

+func semanticVersion() (major, minor, patch, build string) {
+	r := regexp.MustCompile(`v(?P<Major>\d+)\.(?P<Minor>\d+).(?P<Patch>\d+).*\+(?P<CommitsAhead>\d+)`)
+	matches := r.FindStringSubmatch(getVersion())
+	if len(matches) != 5 {
+		return "0", "0", "0", "0"
+	}
+	return matches[1], matches[2], matches[3], matches[4]
+}
+
 func getBranchSuffix() string {
 	bs, err := runError("git", "branch", "-a", "--contains")
 	if err != nil {
@@ -891,7 +974,7 @@ func buildHost() string {
 func buildArch() string {
 	os := goos
 	if os == "darwin" {
-		os = "macosx"
+		os = "macos"
 	}
 	return fmt.Sprintf("%s-%s", os, goarch)
 }
@@ -914,6 +997,10 @@ func runError(cmd string, args ...string) ([]byte, error) {
 }

 func runPrint(cmd string, args ...string) {
+	runPrintInDir(".", cmd, args...)
+}
+
+func runPrintInDir(dir string, cmd string, args ...string) {
 	if debug {
 		t0 := time.Now()
 		log.Println("runPrint:", cmd, strings.Join(args, " "))
@@ -924,6 +1011,7 @@ func runPrint(cmd string, args ...string) {
 	ecmd := exec.Command(cmd, args...)
 	ecmd.Stdout = os.Stdout
 	ecmd.Stderr = os.Stderr
+	ecmd.Dir = dir
 	err := ecmd.Run()
 	if err != nil {
 		log.Fatal(err)
@@ -1085,6 +1173,15 @@ func zipFile(out string, files []archiveFile) {
 	}
 }

+func codesign(target target) {
+	switch goos {
+	case "windows":
+		windowsCodesign(target.BinaryName())
+	case "darwin":
+		macosCodesign(target.BinaryName())
+	}
+}
+
 func macosCodesign(file string) {
 	if pass := os.Getenv("CODESIGN_KEYCHAIN_PASS"); pass != "" {
 		bs, err := runError("security", "unlock-keychain", "-p", pass)
@@ -1143,12 +1240,12 @@ func windowsCodesign(file string) {

 func metalint() {
 	lazyRebuildAssets()
-	runPrint("go", "test", "-run", "Metalint", "./meta")
+	runPrint(goCmd, "test", "-run", "Metalint", "./meta")
 }

 func metalintShort() {
 	lazyRebuildAssets()
-	runPrint("go", "test", "-short", "-run", "Metalint", "./meta")
+	runPrint(goCmd, "test", "-short", "-run", "Metalint", "./meta")
 }

 func temporaryBuildDir() (string, error) {
@@ -1177,93 +1274,17 @@ func temporaryBuildDir() (string, error) {
 	return filepath.Join(tmpDir, base), nil
 }

-func buildGOPATH(gopath string) error {
-	pkg := filepath.Join(gopath, "src/github.com/syncthing/syncthing")
-	dirs := []string{"cmd", "lib", "meta", "script", "test", "vendor"}
-
-	if debug {
-		t0 := time.Now()
-		log.Println("build temporary GOPATH in", gopath)
-		defer func() {
-			log.Println("... in", time.Since(t0))
-		}()
-	}
-
-	// Walk the sources and copy the files into the temporary GOPATH.
-	// Remember which files are supposed to be present so we can clean
-	// out everything else in the next step. The copyFile() step will
-	// only actually copy the file if it doesn't exist or the contents
-	// differ.
-
-	exists := map[string]struct{}{}
-	for _, dir := range dirs {
-		err := filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
-			if err != nil {
-				return err
-			}
-			if info.IsDir() {
-				return nil
-			}
-
-			dst := filepath.Join(pkg, path)
-			exists[dst] = struct{}{}
-
-			if err := copyFile(path, dst, info.Mode()); err != nil {
-				return err
-			}
-
-			return nil
-		})
-		if err != nil {
-			return err
-		}
-	}
-
-	// Walk the temporary GOPATH and remove any files that we wouldn't
-	// have copied there in the previous step.
-
-	filepath.Walk(pkg, func(path string, info os.FileInfo, err error) error {
-		if err != nil {
-			return err
-		}
-		if info.IsDir() {
-			return nil
-		}
-		if _, ok := exists[path]; !ok {
-			os.Remove(path)
-		}
-		return nil
-	})
-
-	return nil
-}
-
-func gopath() string {
-	if gopath := os.Getenv("GOPATH"); gopath != "" {
-		// The env var is set, use that.
-		return gopath
-	}
-
-	// Ask Go what it thinks.
-	bs, err := runError("go", "env", "GOPATH")
-	if err != nil {
-		return ""
-	}
-
-	// We got something. Check if we are in fact available in that location.
-	gopath := string(bs)
-	if _, err := os.Stat(filepath.Join(gopath, "src/github.com/syncthing/syncthing/build.go")); err == nil {
-		// That seems to be the gopath.
-		return gopath
-	}
-
-	// The gopath is not valid.
-	return ""
-}
-
 func (t target) BinaryName() string {
 	if goos == "windows" {
 		return t.binaryName + ".exe"
 	}
 	return t.binaryName
 }
+
+func protobufVersion() string {
+	bs, err := runError(goCmd, "list", "-f", "{{.Version}}", "-m", "github.com/gogo/protobuf")
+	if err != nil {
+		log.Fatal("Getting protobuf version:", err)
+	}
+	return string(bs)
+}
--- a/build.sh
+++ b/build.sh
@@ -59,8 +59,8 @@ case "${1:-default}" in
 		go run script/authors.go
 		build transifex
 		pushd man ; ./refresh.sh ; popd
-		git add -A gui man
-		git commit -m 'gui, man: Update docs & translations'
+		git add -A gui man AUTHORS
+		git commit -m 'gui, man, authors: Update docs, translations, and contributors'
 		;;

 	noupgrade)
--- a/cmd/stbench/main.go
+++ b/cmd/stbench/main.go
@@ -1,143 +0,0 @@
-// Copyright (C) 2016 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-// This doesn't build on Windows due to the Rusage stuff.
-
-// +build !windows
-
-package main
-
-import (
-	"flag"
-	"fmt"
-	"log"
-	"runtime"
-	"syscall"
-	"time"
-
-	"github.com/syncthing/syncthing/lib/rc"
-)
-
-var homeDir = "h1"
-var syncthingBin = "./bin/syncthing"
-var test = "scan"
-
-func main() {
-	flag.StringVar(&homeDir, "home", homeDir, "Home directory location")
-	flag.StringVar(&syncthingBin, "bin", syncthingBin, "Binary location")
-	flag.StringVar(&test, "test", test, "Test to run")
-	flag.Parse()
-
-	switch test {
-	case "scan":
-		// scan measures the resource usage required to perform the initial
-		// scan, without cleaning away the database first.
-		testScan()
-	}
-}
-
-// testScan starts a process and reports on the resource usage required to
-// perform the initial scan.
-func testScan() {
-	log.Println("Starting...")
-	p := rc.NewProcess("127.0.0.1:8081")
-	if err := p.Start(syncthingBin, "-home", homeDir, "-no-browser"); err != nil {
-		log.Println(err)
-		return
-	}
-	defer p.Stop()
-
-	wallTime := awaitScanComplete(p)
-
-	report(p, wallTime)
-}
-
-// awaitScanComplete waits for a folder to transition idle->scanning and
-// then scanning->idle and returns the time taken for the scan.
-func awaitScanComplete(p *rc.Process) time.Duration {
-	log.Println("Awaiting scan completion...")
-	var t0, t1 time.Time
-	lastEvent := 0
-loop:
-	for {
-		evs, err := p.Events(lastEvent)
-		if err != nil {
-			continue
-		}
-
-		for _, ev := range evs {
-			if ev.Type == "StateChanged" {
-				data := ev.Data.(map[string]interface{})
-				log.Println(ev)
-
-				if data["to"].(string) == "scanning" {
-					t0 = ev.Time
-					continue
-				}
-
-				if !t0.IsZero() && data["to"].(string) == "idle" {
-					t1 = ev.Time
-					break loop
-				}
-			}
-			lastEvent = ev.ID
-		}
-
-		time.Sleep(250 * time.Millisecond)
-	}
-
-	return t1.Sub(t0)
-}
-
-// report stops the given process and reports on its resource usage in two
-// ways: human readable to stderr, and CSV to stdout.
-func report(p *rc.Process, wallTime time.Duration) {
-	sv, err := p.SystemVersion()
-	if err != nil {
-		log.Println(err)
-		return
-	}
-
-	ss, err := p.SystemStatus()
-	if err != nil {
-		log.Println(err)
-		return
-	}
-
-	proc, err := p.Stop()
-	if err != nil {
-		return
-	}
-
-	rusage, ok := proc.SysUsage().(*syscall.Rusage)
-	if !ok {
-		return
-	}
-
-	log.Println("Version:", sv.Version)
-	log.Println("Alloc:", ss.Alloc/1024, "KiB")
-	log.Println("Sys:", ss.Sys/1024, "KiB")
-	log.Println("Goroutines:", ss.Goroutines)
-	log.Println("Wall time:", wallTime)
-	log.Println("Utime:", time.Duration(rusage.Utime.Nano()))
-	log.Println("Stime:", time.Duration(rusage.Stime.Nano()))
-	if runtime.GOOS == "darwin" {
-		// Darwin reports in bytes, Linux seems to report in KiB even
-		// though the manpage says otherwise.
-		rusage.Maxrss /= 1024
-	}
-	log.Println("MaxRSS:", rusage.Maxrss, "KiB")
-
-	fmt.Printf("%s,%d,%d,%d,%.02f,%.02f,%.02f,%d\n",
-		sv.Version,
-		ss.Alloc/1024,
-		ss.Sys/1024,
-		ss.Goroutines,
-		wallTime.Seconds(),
-		time.Duration(rusage.Utime.Nano()).Seconds(),
-		time.Duration(rusage.Stime.Nano()).Seconds(),
-		rusage.Maxrss)
-}
--- a/cmd/stcli/LICENSE
+++ b/cmd/stcli/LICENSE
@@ -1,19 +0,0 @@
-Copyright (C) 2014 Audrius Butkevičius
-
-Permission is hereby granted, free of charge, to any person obtaining a copy of
-this software and associated documentation files (the "Software"), to deal in
-the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-of the Software, and to permit persons to whom the Software is furnished to do
-so, subject to the following conditions:
-
- The above copyright notice and this permission notice shall be included in
-  all copies or substantial portions of the Software.
-
-THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-SOFTWARE.
--- a/cmd/stcli/client.go
+++ b/cmd/stcli/client.go
@@ -1,115 +1,95 @@
-// Copyright (C) 2014 Audrius Butkevičius
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.

 package main

 import (
 	"bytes"
+	"context"
 	"crypto/tls"
+	"fmt"
+	"net"
 	"net/http"
 	"strings"

-	"github.com/AudriusButkevicius/cli"
+	"github.com/syncthing/syncthing/lib/config"
 )

 type APIClient struct {
-	httpClient http.Client
-	endpoint   string
-	apikey     string
-	username   string
-	password   string
-	id         string
-	csrf       string
+	http.Client
+	cfg    config.GUIConfiguration
+	apikey string
 }

-var instance *APIClient
-
-func getClient(c *cli.Context) *APIClient {
-	if instance != nil {
-		return instance
-	}
-	endpoint := c.GlobalString("endpoint")
-	if !strings.HasPrefix(endpoint, "http") {
-		endpoint = "http://" + endpoint
-	}
+func getClient(cfg config.GUIConfiguration) *APIClient {
 	httpClient := http.Client{
 		Transport: &http.Transport{
 			TLSClientConfig: &tls.Config{
-				InsecureSkipVerify: c.GlobalBool("insecure"),
+				InsecureSkipVerify: true,
+			},
+			DialContext: func(_ context.Context, _, _ string) (net.Conn, error) {
+				return net.Dial(cfg.Network(), cfg.Address())
 			},
 		},
 	}
-	client := APIClient{
-		httpClient: httpClient,
-		endpoint:   endpoint,
-		apikey:     c.GlobalString("apikey"),
-		username:   c.GlobalString("username"),
-		password:   c.GlobalString("password"),
+	return &APIClient{
+		Client: httpClient,
+		cfg:    cfg,
+		apikey: cfg.APIKey,
 	}
-
-	if client.apikey == "" {
-		request, err := http.NewRequest("GET", client.endpoint, nil)
-		die(err)
-		response := client.handleRequest(request)
-		client.id = response.Header.Get("X-Syncthing-ID")
-		if client.id == "" {
-			die("Failed to get device ID")
-		}
-		for _, item := range response.Cookies() {
-			if item.Name == "CSRF-Token-"+client.id[:5] {
-				client.csrf = item.Value
-				goto csrffound
-			}
-		}
-		die("Failed to get CSRF token")
-	csrffound:
-	}
-	instance = &client
-	return &client
 }

-func (client *APIClient) handleRequest(request *http.Request) *http.Response {
-	if client.apikey != "" {
-		request.Header.Set("X-API-Key", client.apikey)
+func (c *APIClient) Endpoint() string {
+	if c.cfg.Network() == "unix" {
+		return "http://unix/"
 	}
-	if client.username != "" || client.password != "" {
-		request.SetBasicAuth(client.username, client.password)
-	}
-	if client.csrf != "" {
-		request.Header.Set("X-CSRF-Token-"+client.id[:5], client.csrf)
+	url := c.cfg.URL()
+	if !strings.HasSuffix(url, "/") {
+		url += "/"
 	}
+	return url
+}

-	response, err := client.httpClient.Do(request)
-	die(err)
+func (c *APIClient) Do(req *http.Request) (*http.Response, error) {
+	req.Header.Set("X-API-Key", c.apikey)
+	resp, err := c.Client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	return resp, checkResponse(resp)
+}

+func (c *APIClient) Get(url string) (*http.Response, error) {
+	request, err := http.NewRequest("GET", c.Endpoint()+"rest/"+url, nil)
+	if err != nil {
+		return nil, err
+	}
+	return c.Do(request)
+}
+
+func (c *APIClient) Post(url, body string) (*http.Response, error) {
+	request, err := http.NewRequest("POST", c.Endpoint()+"rest/"+url, bytes.NewBufferString(body))
+	if err != nil {
+		return nil, err
+	}
+	return c.Do(request)
+}
+
+func checkResponse(response *http.Response) error {
 	if response.StatusCode == 404 {
-		die("Invalid endpoint or API call")
-	} else if response.StatusCode == 401 {
-		die("Invalid username or password")
+		return fmt.Errorf("Invalid endpoint or API call")
 	} else if response.StatusCode == 403 {
-		if client.apikey == "" {
-			die("Invalid CSRF token")
-		}
-		die("Invalid API key")
+		return fmt.Errorf("Invalid API key")
 	} else if response.StatusCode != 200 {
-		body := strings.TrimSpace(string(responseToBArray(response)))
-		if body != "" {
-			die(body)
+		data, err := responseToBArray(response)
+		if err != nil {
+			return err
 		}
-		die("Unknown HTTP status returned: " + response.Status)
+		body := strings.TrimSpace(string(data))
+		return fmt.Errorf("Unexpected HTTP status returned: %s\n%s", response.Status, body)
 	}
-	return response
-}
-
-func httpGet(c *cli.Context, url string) *http.Response {
-	client := getClient(c)
-	request, err := http.NewRequest("GET", client.endpoint+"/rest/"+url, nil)
-	die(err)
-	return client.handleRequest(request)
-}
-
-func httpPost(c *cli.Context, url string, body string) *http.Response {
-	client := getClient(c)
-	request, err := http.NewRequest("POST", client.endpoint+"/rest/"+url, bytes.NewBufferString(body))
-	die(err)
-	return client.handleRequest(request)
+	return nil
 }
--- a/cmd/stcli/cmd_devices.go
+++ b/cmd/stcli/cmd_devices.go
@@ -1,188 +0,0 @@
-// Copyright (C) 2014 Audrius Butkevičius
-
-package main
-
-import (
-	"fmt"
-	"strings"
-
-	"github.com/AudriusButkevicius/cli"
-	"github.com/syncthing/syncthing/lib/config"
-)
-
-func init() {
-	cliCommands = append(cliCommands, cli.Command{
-		Name:     "devices",
-		HideHelp: true,
-		Usage:    "Device command group",
-		Subcommands: []cli.Command{
-			{
-				Name:     "list",
-				Usage:    "List registered devices",
-				Requires: &cli.Requires{},
-				Action:   devicesList,
-			},
-			{
-				Name:     "add",
-				Usage:    "Add a new device",
-				Requires: &cli.Requires{"device id", "device name?"},
-				Action:   devicesAdd,
-			},
-			{
-				Name:     "remove",
-				Usage:    "Remove an existing device",
-				Requires: &cli.Requires{"device id"},
-				Action:   devicesRemove,
-			},
-			{
-				Name:     "get",
-				Usage:    "Get a property of a device",
-				Requires: &cli.Requires{"device id", "property"},
-				Action:   devicesGet,
-			},
-			{
-				Name:     "set",
-				Usage:    "Set a property of a device",
-				Requires: &cli.Requires{"device id", "property", "value..."},
-				Action:   devicesSet,
-			},
-		},
-	})
-}
-
-func devicesList(c *cli.Context) {
-	cfg := getConfig(c)
-	first := true
-	writer := newTableWriter()
-	for _, device := range cfg.Devices {
-		if !first {
-			fmt.Fprintln(writer)
-		}
-		fmt.Fprintln(writer, "ID:\t", device.DeviceID, "\t")
-		fmt.Fprintln(writer, "Name:\t", device.Name, "\t(name)")
-		fmt.Fprintln(writer, "Address:\t", strings.Join(device.Addresses, " "), "\t(address)")
-		fmt.Fprintln(writer, "Compression:\t", device.Compression, "\t(compression)")
-		fmt.Fprintln(writer, "Certificate name:\t", device.CertName, "\t(certname)")
-		fmt.Fprintln(writer, "Introducer:\t", device.Introducer, "\t(introducer)")
-		first = false
-	}
-	writer.Flush()
-}
-
-func devicesAdd(c *cli.Context) {
-	nid := c.Args()[0]
-	id := parseDeviceID(nid)
-
-	newDevice := config.DeviceConfiguration{
-		DeviceID:  id,
-		Name:      nid,
-		Addresses: []string{"dynamic"},
-	}
-
-	if len(c.Args()) > 1 {
-		newDevice.Name = c.Args()[1]
-	}
-
-	if len(c.Args()) > 2 {
-		addresses := c.Args()[2:]
-		for _, item := range addresses {
-			if item == "dynamic" {
-				continue
-			}
-			validAddress(item)
-		}
-		newDevice.Addresses = addresses
-	}
-
-	cfg := getConfig(c)
-	for _, device := range cfg.Devices {
-		if device.DeviceID == id {
-			die("Device " + nid + " already exists")
-		}
-	}
-	cfg.Devices = append(cfg.Devices, newDevice)
-	setConfig(c, cfg)
-}
-
-func devicesRemove(c *cli.Context) {
-	nid := c.Args()[0]
-	id := parseDeviceID(nid)
-	if nid == getMyID(c) {
-		die("Cannot remove yourself")
-	}
-	cfg := getConfig(c)
-	for i, device := range cfg.Devices {
-		if device.DeviceID == id {
-			last := len(cfg.Devices) - 1
-			cfg.Devices[i] = cfg.Devices[last]
-			cfg.Devices = cfg.Devices[:last]
-			setConfig(c, cfg)
-			return
-		}
-	}
-	die("Device " + nid + " not found")
-}
-
-func devicesGet(c *cli.Context) {
-	nid := c.Args()[0]
-	id := parseDeviceID(nid)
-	arg := c.Args()[1]
-	cfg := getConfig(c)
-	for _, device := range cfg.Devices {
-		if device.DeviceID != id {
-			continue
-		}
-		switch strings.ToLower(arg) {
-		case "name":
-			fmt.Println(device.Name)
-		case "address":
-			fmt.Println(strings.Join(device.Addresses, "\n"))
-		case "compression":
-			fmt.Println(device.Compression.String())
-		case "certname":
-			fmt.Println(device.CertName)
-		case "introducer":
-			fmt.Println(device.Introducer)
-		default:
-			die("Invalid property: " + arg + "\nAvailable properties: name, address, compression, certname, introducer")
-		}
-		return
-	}
-	die("Device " + nid + " not found")
-}
-
-func devicesSet(c *cli.Context) {
-	nid := c.Args()[0]
-	id := parseDeviceID(nid)
-	arg := c.Args()[1]
-	config := getConfig(c)
-	for i, device := range config.Devices {
-		if device.DeviceID != id {
-			continue
-		}
-		switch strings.ToLower(arg) {
-		case "name":
-			config.Devices[i].Name = strings.Join(c.Args()[2:], " ")
-		case "address":
-			for _, item := range c.Args()[2:] {
-				if item == "dynamic" {
-					continue
-				}
-				validAddress(item)
-			}
-			config.Devices[i].Addresses = c.Args()[2:]
-		case "compression":
-			err := config.Devices[i].Compression.UnmarshalText([]byte(c.Args()[2]))
-			die(err)
-		case "certname":
-			config.Devices[i].CertName = strings.Join(c.Args()[2:], " ")
-		case "introducer":
-			config.Devices[i].Introducer = parseBool(c.Args()[2])
-		default:
-			die("Invalid property: " + arg + "\nAvailable properties: name, address, compression, certname, introducer")
-		}
-		setConfig(c, config)
-		return
-	}
-	die("Device " + nid + " not found")
-}
--- a/cmd/stcli/cmd_errors.go
+++ b/cmd/stcli/cmd_errors.go
@@ -1,67 +0,0 @@
-// Copyright (C) 2014 Audrius Butkevičius
-
-package main
-
-import (
-	"encoding/json"
-	"fmt"
-	"strings"
-
-	"github.com/AudriusButkevicius/cli"
-)
-
-func init() {
-	cliCommands = append(cliCommands, cli.Command{
-		Name:     "errors",
-		HideHelp: true,
-		Usage:    "Error command group",
-		Subcommands: []cli.Command{
-			{
-				Name:     "show",
-				Usage:    "Show pending errors",
-				Requires: &cli.Requires{},
-				Action:   errorsShow,
-			},
-			{
-				Name:     "push",
-				Usage:    "Push an error to active clients",
-				Requires: &cli.Requires{"error message..."},
-				Action:   errorsPush,
-			},
-			{
-				Name:     "clear",
-				Usage:    "Clear pending errors",
-				Requires: &cli.Requires{},
-				Action:   wrappedHTTPPost("system/error/clear"),
-			},
-		},
-	})
-}
-
-func errorsShow(c *cli.Context) {
-	response := httpGet(c, "system/error")
-	var data map[string][]map[string]interface{}
-	json.Unmarshal(responseToBArray(response), &data)
-	writer := newTableWriter()
-	for _, item := range data["errors"] {
-		time := item["time"].(string)[:19]
-		time = strings.Replace(time, "T", " ", 1)
-		err := item["error"].(string)
-		err = strings.TrimSpace(err)
-		fmt.Fprintln(writer, time+":\t"+err)
-	}
-	writer.Flush()
-}
-
-func errorsPush(c *cli.Context) {
-	err := strings.Join(c.Args(), " ")
-	response := httpPost(c, "system/error", strings.TrimSpace(err))
-	if response.StatusCode != 200 {
-		err = fmt.Sprint("Failed to push error\nStatus code: ", response.StatusCode)
-		body := string(responseToBArray(response))
-		if body != "" {
-			err += "\nBody: " + body
-		}
-		die(err)
-	}
-}
--- a/cmd/stcli/cmd_folders.go
+++ b/cmd/stcli/cmd_folders.go
@@ -1,361 +0,0 @@
-// Copyright (C) 2014 Audrius Butkevičius
-
-package main
-
-import (
-	"fmt"
-	"path/filepath"
-	"strings"
-
-	"github.com/AudriusButkevicius/cli"
-	"github.com/syncthing/syncthing/lib/config"
-	"github.com/syncthing/syncthing/lib/fs"
-)
-
-func init() {
-	cliCommands = append(cliCommands, cli.Command{
-		Name:     "folders",
-		HideHelp: true,
-		Usage:    "Folder command group",
-		Subcommands: []cli.Command{
-			{
-				Name:     "list",
-				Usage:    "List available folders",
-				Requires: &cli.Requires{},
-				Action:   foldersList,
-			},
-			{
-				Name:     "add",
-				Usage:    "Add a new folder",
-				Requires: &cli.Requires{"folder id", "directory"},
-				Action:   foldersAdd,
-			},
-			{
-				Name:     "remove",
-				Usage:    "Remove an existing folder",
-				Requires: &cli.Requires{"folder id"},
-				Action:   foldersRemove,
-			},
-			{
-				Name:     "override",
-				Usage:    "Override changes from other nodes for a master folder",
-				Requires: &cli.Requires{"folder id"},
-				Action:   foldersOverride,
-			},
-			{
-				Name:     "get",
-				Usage:    "Get a property of a folder",
-				Requires: &cli.Requires{"folder id", "property"},
-				Action:   foldersGet,
-			},
-			{
-				Name:     "set",
-				Usage:    "Set a property of a folder",
-				Requires: &cli.Requires{"folder id", "property", "value..."},
-				Action:   foldersSet,
-			},
-			{
-				Name:     "unset",
-				Usage:    "Unset a property of a folder",
-				Requires: &cli.Requires{"folder id", "property"},
-				Action:   foldersUnset,
-			},
-			{
-				Name:     "devices",
-				Usage:    "Folder devices command group",
-				HideHelp: true,
-				Subcommands: []cli.Command{
-					{
-						Name:     "list",
-						Usage:    "List of devices which the folder is shared with",
-						Requires: &cli.Requires{"folder id"},
-						Action:   foldersDevicesList,
-					},
-					{
-						Name:     "add",
-						Usage:    "Share a folder with a device",
-						Requires: &cli.Requires{"folder id", "device id"},
-						Action:   foldersDevicesAdd,
-					},
-					{
-						Name:     "remove",
-						Usage:    "Unshare a folder with a device",
-						Requires: &cli.Requires{"folder id", "device id"},
-						Action:   foldersDevicesRemove,
-					},
-					{
-						Name:     "clear",
-						Usage:    "Unshare a folder with all devices",
-						Requires: &cli.Requires{"folder id"},
-						Action:   foldersDevicesClear,
-					},
-				},
-			},
-		},
-	})
-}
-
-func foldersList(c *cli.Context) {
-	cfg := getConfig(c)
-	first := true
-	writer := newTableWriter()
-	for _, folder := range cfg.Folders {
-		if !first {
-			fmt.Fprintln(writer)
-		}
-		fs := folder.Filesystem()
-		fmt.Fprintln(writer, "ID:\t", folder.ID, "\t")
-		fmt.Fprintln(writer, "Path:\t", fs.URI(), "\t(directory)")
-		fmt.Fprintln(writer, "Path type:\t", fs.Type(), "\t(directory-type)")
-		fmt.Fprintln(writer, "Folder type:\t", folder.Type, "\t(type)")
-		fmt.Fprintln(writer, "Ignore permissions:\t", folder.IgnorePerms, "\t(permissions)")
-		fmt.Fprintln(writer, "Rescan interval in seconds:\t", folder.RescanIntervalS, "\t(rescan)")
-
-		if folder.Versioning.Type != "" {
-			fmt.Fprintln(writer, "Versioning:\t", folder.Versioning.Type, "\t(versioning)")
-			for key, value := range folder.Versioning.Params {
-				fmt.Fprintf(writer, "Versioning %s:\t %s \t(versioning-%s)\n", key, value, key)
-			}
-		}
-		first = false
-	}
-	writer.Flush()
-}
-
-func foldersAdd(c *cli.Context) {
-	cfg := getConfig(c)
-	abs, err := filepath.Abs(c.Args()[1])
-	die(err)
-	folder := config.FolderConfiguration{
-		ID:             c.Args()[0],
-		Path:           filepath.Clean(abs),
-		FilesystemType: fs.FilesystemTypeBasic,
-	}
-	cfg.Folders = append(cfg.Folders, folder)
-	setConfig(c, cfg)
-}
-
-func foldersRemove(c *cli.Context) {
-	cfg := getConfig(c)
-	rid := c.Args()[0]
-	for i, folder := range cfg.Folders {
-		if folder.ID == rid {
-			last := len(cfg.Folders) - 1
-			cfg.Folders[i] = cfg.Folders[last]
-			cfg.Folders = cfg.Folders[:last]
-			setConfig(c, cfg)
-			return
-		}
-	}
-	die("Folder " + rid + " not found")
-}
-
-func foldersOverride(c *cli.Context) {
-	cfg := getConfig(c)
-	rid := c.Args()[0]
-	for _, folder := range cfg.Folders {
-		if folder.ID == rid && folder.Type == config.FolderTypeSendOnly {
-			response := httpPost(c, "db/override", "")
-			if response.StatusCode != 200 {
-				err := fmt.Sprint("Failed to override changes\nStatus code: ", response.StatusCode)
-				body := string(responseToBArray(response))
-				if body != "" {
-					err += "\nBody: " + body
-				}
-				die(err)
-			}
-			return
-		}
-	}
-	die("Folder " + rid + " not found or folder not master")
-}
-
-func foldersGet(c *cli.Context) {
-	cfg := getConfig(c)
-	rid := c.Args()[0]
-	arg := strings.ToLower(c.Args()[1])
-	for _, folder := range cfg.Folders {
-		if folder.ID != rid {
-			continue
-		}
-		if strings.HasPrefix(arg, "versioning-") {
-			arg = arg[11:]
-			value, ok := folder.Versioning.Params[arg]
-			if ok {
-				fmt.Println(value)
-				return
-			}
-			die("Versioning property " + c.Args()[1][11:] + " not found")
-		}
-		switch arg {
-		case "directory":
-			fmt.Println(folder.Filesystem().URI())
-		case "directory-type":
-			fmt.Println(folder.Filesystem().Type())
-		case "type":
-			fmt.Println(folder.Type)
-		case "permissions":
-			fmt.Println(folder.IgnorePerms)
-		case "rescan":
-			fmt.Println(folder.RescanIntervalS)
-		case "versioning":
-			if folder.Versioning.Type != "" {
-				fmt.Println(folder.Versioning.Type)
-			}
-		default:
-			die("Invalid property: " + c.Args()[1] + "\nAvailable properties: directory, directory-type, type, permissions, versioning, versioning-<key>")
-		}
-		return
-	}
-	die("Folder " + rid + " not found")
-}
-
-func foldersSet(c *cli.Context) {
-	rid := c.Args()[0]
-	arg := strings.ToLower(c.Args()[1])
-	val := strings.Join(c.Args()[2:], " ")
-	cfg := getConfig(c)
-	for i, folder := range cfg.Folders {
-		if folder.ID != rid {
-			continue
-		}
-		if strings.HasPrefix(arg, "versioning-") {
-			cfg.Folders[i].Versioning.Params[arg[11:]] = val
-			setConfig(c, cfg)
-			return
-		}
-		switch arg {
-		case "directory":
-			cfg.Folders[i].Path = val
-		case "directory-type":
-			var fsType fs.FilesystemType
-			fsType.UnmarshalText([]byte(val))
-			cfg.Folders[i].FilesystemType = fsType
-		case "type":
-			var t config.FolderType
-			if err := t.UnmarshalText([]byte(val)); err != nil {
-				die("Invalid folder type: " + err.Error())
-			}
-			cfg.Folders[i].Type = t
-		case "permissions":
-			cfg.Folders[i].IgnorePerms = parseBool(val)
-		case "rescan":
-			cfg.Folders[i].RescanIntervalS = parseInt(val)
-		case "versioning":
-			cfg.Folders[i].Versioning.Type = val
-		default:
-			die("Invalid property: " + c.Args()[1] + "\nAvailable properties: directory, master, permissions, versioning, versioning-<key>")
-		}
-		setConfig(c, cfg)
-		return
-	}
-	die("Folder " + rid + " not found")
-}
-
-func foldersUnset(c *cli.Context) {
-	rid := c.Args()[0]
-	arg := strings.ToLower(c.Args()[1])
-	cfg := getConfig(c)
-	for i, folder := range cfg.Folders {
-		if folder.ID != rid {
-			continue
-		}
-		if strings.HasPrefix(arg, "versioning-") {
-			arg = arg[11:]
-			if _, ok := folder.Versioning.Params[arg]; ok {
-				delete(cfg.Folders[i].Versioning.Params, arg)
-				setConfig(c, cfg)
-				return
-			}
-			die("Versioning property " + c.Args()[1][11:] + " not found")
-		}
-		switch arg {
-		case "versioning":
-			cfg.Folders[i].Versioning.Type = ""
-			cfg.Folders[i].Versioning.Params = make(map[string]string)
-		default:
-			die("Invalid property: " + c.Args()[1] + "\nAvailable properties: versioning, versioning-<key>")
-		}
-		setConfig(c, cfg)
-		return
-	}
-	die("Folder " + rid + " not found")
-}
-
-func foldersDevicesList(c *cli.Context) {
-	rid := c.Args()[0]
-	cfg := getConfig(c)
-	for _, folder := range cfg.Folders {
-		if folder.ID != rid {
-			continue
-		}
-		for _, device := range folder.Devices {
-			fmt.Println(device.DeviceID)
-		}
-		return
-	}
-	die("Folder " + rid + " not found")
-}
-
-func foldersDevicesAdd(c *cli.Context) {
-	rid := c.Args()[0]
-	nid := parseDeviceID(c.Args()[1])
-	cfg := getConfig(c)
-	for i, folder := range cfg.Folders {
-		if folder.ID != rid {
-			continue
-		}
-		for _, device := range folder.Devices {
-			if device.DeviceID == nid {
-				die("Device " + c.Args()[1] + " is already part of this folder")
-			}
-		}
-		for _, device := range cfg.Devices {
-			if device.DeviceID == nid {
-				cfg.Folders[i].Devices = append(folder.Devices, config.FolderDeviceConfiguration{
-					DeviceID: device.DeviceID,
-				})
-				setConfig(c, cfg)
-				return
-			}
-		}
-		die("Device " + c.Args()[1] + " not found in device list")
-	}
-	die("Folder " + rid + " not found")
-}
-
-func foldersDevicesRemove(c *cli.Context) {
-	rid := c.Args()[0]
-	nid := parseDeviceID(c.Args()[1])
-	cfg := getConfig(c)
-	for ri, folder := range cfg.Folders {
-		if folder.ID != rid {
-			continue
-		}
-		for ni, device := range folder.Devices {
-			if device.DeviceID == nid {
-				last := len(folder.Devices) - 1
-				cfg.Folders[ri].Devices[ni] = folder.Devices[last]
-				cfg.Folders[ri].Devices = cfg.Folders[ri].Devices[:last]
-				setConfig(c, cfg)
-				return
-			}
-		}
-		die("Device " + c.Args()[1] + " not found")
-	}
-	die("Folder " + rid + " not found")
-}
-
-func foldersDevicesClear(c *cli.Context) {
-	rid := c.Args()[0]
-	cfg := getConfig(c)
-	for i, folder := range cfg.Folders {
-		if folder.ID != rid {
-			continue
-		}
-		cfg.Folders[i].Devices = []config.FolderDeviceConfiguration{}
-		setConfig(c, cfg)
-		return
-	}
-	die("Folder " + rid + " not found")
-}
--- a/cmd/stcli/cmd_general.go
+++ b/cmd/stcli/cmd_general.go
@@ -1,78 +0,0 @@
-// Copyright (C) 2014 Audrius Butkevičius
-
-package main
-
-import (
-	"encoding/json"
-	"fmt"
-
-	"github.com/AudriusButkevicius/cli"
-)
-
-func init() {
-	cliCommands = append(cliCommands, []cli.Command{
-		{
-			Name:     "id",
-			Usage:    "Get ID of the Syncthing client",
-			Requires: &cli.Requires{},
-			Action:   generalID,
-		},
-		{
-			Name:     "status",
-			Usage:    "Configuration status, whether or not a restart is required for changes to take effect",
-			Requires: &cli.Requires{},
-			Action:   generalStatus,
-		},
-		{
-			Name:     "restart",
-			Usage:    "Restart syncthing",
-			Requires: &cli.Requires{},
-			Action:   wrappedHTTPPost("system/restart"),
-		},
-		{
-			Name:     "shutdown",
-			Usage:    "Shutdown syncthing",
-			Requires: &cli.Requires{},
-			Action:   wrappedHTTPPost("system/shutdown"),
-		},
-		{
-			Name:     "reset",
-			Usage:    "Reset syncthing deleting all folders and devices",
-			Requires: &cli.Requires{},
-			Action:   wrappedHTTPPost("system/reset"),
-		},
-		{
-			Name:     "upgrade",
-			Usage:    "Upgrade syncthing (if a newer version is available)",
-			Requires: &cli.Requires{},
-			Action:   wrappedHTTPPost("system/upgrade"),
-		},
-		{
-			Name:     "version",
-			Usage:    "Syncthing client version",
-			Requires: &cli.Requires{},
-			Action:   generalVersion,
-		},
-	}...)
-}
-
-func generalID(c *cli.Context) {
-	fmt.Println(getMyID(c))
-}
-
-func generalStatus(c *cli.Context) {
-	response := httpGet(c, "system/config/insync")
-	var status struct{ ConfigInSync bool }
-	json.Unmarshal(responseToBArray(response), &status)
-	if !status.ConfigInSync {
-		die("Config out of sync")
-	}
-	fmt.Println("Config in sync")
-}
-
-func generalVersion(c *cli.Context) {
-	response := httpGet(c, "system/version")
-	version := make(map[string]interface{})
-	json.Unmarshal(responseToBArray(response), &version)
-	prettyPrintJSON(version)
-}
--- a/cmd/stcli/cmd_gui.go
+++ b/cmd/stcli/cmd_gui.go
@@ -1,127 +0,0 @@
-// Copyright (C) 2014 Audrius Butkevičius
-
-package main
-
-import (
-	"fmt"
-	"strings"
-
-	"github.com/AudriusButkevicius/cli"
-)
-
-func init() {
-	cliCommands = append(cliCommands, cli.Command{
-		Name:     "gui",
-		HideHelp: true,
-		Usage:    "GUI command group",
-		Subcommands: []cli.Command{
-			{
-				Name:     "dump",
-				Usage:    "Show all GUI configuration settings",
-				Requires: &cli.Requires{},
-				Action:   guiDump,
-			},
-			{
-				Name:     "get",
-				Usage:    "Get a GUI configuration setting",
-				Requires: &cli.Requires{"setting"},
-				Action:   guiGet,
-			},
-			{
-				Name:     "set",
-				Usage:    "Set a GUI configuration setting",
-				Requires: &cli.Requires{"setting", "value"},
-				Action:   guiSet,
-			},
-			{
-				Name:     "unset",
-				Usage:    "Unset a GUI configuration setting",
-				Requires: &cli.Requires{"setting"},
-				Action:   guiUnset,
-			},
-		},
-	})
-}
-
-func guiDump(c *cli.Context) {
-	cfg := getConfig(c).GUI
-	writer := newTableWriter()
-	fmt.Fprintln(writer, "Enabled:\t", cfg.Enabled, "\t(enabled)")
-	fmt.Fprintln(writer, "Use HTTPS:\t", cfg.UseTLS(), "\t(tls)")
-	fmt.Fprintln(writer, "Listen Addresses:\t", cfg.Address(), "\t(address)")
-	if cfg.User != "" {
-		fmt.Fprintln(writer, "Authentication User:\t", cfg.User, "\t(username)")
-		fmt.Fprintln(writer, "Authentication Password:\t", cfg.Password, "\t(password)")
-	}
-	if cfg.APIKey != "" {
-		fmt.Fprintln(writer, "API Key:\t", cfg.APIKey, "\t(apikey)")
-	}
-	writer.Flush()
-}
-
-func guiGet(c *cli.Context) {
-	cfg := getConfig(c).GUI
-	arg := c.Args()[0]
-	switch strings.ToLower(arg) {
-	case "enabled":
-		fmt.Println(cfg.Enabled)
-	case "tls":
-		fmt.Println(cfg.UseTLS())
-	case "address":
-		fmt.Println(cfg.Address())
-	case "user":
-		if cfg.User != "" {
-			fmt.Println(cfg.User)
-		}
-	case "password":
-		if cfg.User != "" {
-			fmt.Println(cfg.Password)
-		}
-	case "apikey":
-		if cfg.APIKey != "" {
-			fmt.Println(cfg.APIKey)
-		}
-	default:
-		die("Invalid setting: " + arg + "\nAvailable settings: enabled, tls, address, user, password, apikey")
-	}
-}
-
-func guiSet(c *cli.Context) {
-	cfg := getConfig(c)
-	arg := c.Args()[0]
-	val := c.Args()[1]
-	switch strings.ToLower(arg) {
-	case "enabled":
-		cfg.GUI.Enabled = parseBool(val)
-	case "tls":
-		cfg.GUI.RawUseTLS = parseBool(val)
-	case "address":
-		validAddress(val)
-		cfg.GUI.RawAddress = val
-	case "user":
-		cfg.GUI.User = val
-	case "password":
-		cfg.GUI.Password = val
-	case "apikey":
-		cfg.GUI.APIKey = val
-	default:
-		die("Invalid setting: " + arg + "\nAvailable settings: enabled, tls, address, user, password, apikey")
-	}
-	setConfig(c, cfg)
-}
-
-func guiUnset(c *cli.Context) {
-	cfg := getConfig(c)
-	arg := c.Args()[0]
-	switch strings.ToLower(arg) {
-	case "user":
-		cfg.GUI.User = ""
-	case "password":
-		cfg.GUI.Password = ""
-	case "apikey":
-		cfg.GUI.APIKey = ""
-	default:
-		die("Invalid setting: " + arg + "\nAvailable settings: user, password, apikey")
-	}
-	setConfig(c, cfg)
-}
--- a/cmd/stcli/cmd_options.go
+++ b/cmd/stcli/cmd_options.go
@@ -1,173 +0,0 @@
-// Copyright (C) 2014 Audrius Butkevičius
-
-package main
-
-import (
-	"fmt"
-	"strings"
-
-	"github.com/AudriusButkevicius/cli"
-)
-
-func init() {
-	cliCommands = append(cliCommands, cli.Command{
-		Name:     "options",
-		HideHelp: true,
-		Usage:    "Options command group",
-		Subcommands: []cli.Command{
-			{
-				Name:     "dump",
-				Usage:    "Show all Syncthing option settings",
-				Requires: &cli.Requires{},
-				Action:   optionsDump,
-			},
-			{
-				Name:     "get",
-				Usage:    "Get a Syncthing option setting",
-				Requires: &cli.Requires{"setting"},
-				Action:   optionsGet,
-			},
-			{
-				Name:     "set",
-				Usage:    "Set a Syncthing option setting",
-				Requires: &cli.Requires{"setting", "value..."},
-				Action:   optionsSet,
-			},
-		},
-	})
-}
-
-func optionsDump(c *cli.Context) {
-	cfg := getConfig(c).Options
-	writer := newTableWriter()
-
-	fmt.Fprintln(writer, "Sync protocol listen addresses:\t", strings.Join(cfg.ListenAddresses, " "), "\t(addresses)")
-	fmt.Fprintln(writer, "Global discovery enabled:\t", cfg.GlobalAnnEnabled, "\t(globalannenabled)")
-	fmt.Fprintln(writer, "Global discovery servers:\t", strings.Join(cfg.GlobalAnnServers, " "), "\t(globalannserver)")
-
-	fmt.Fprintln(writer, "Local discovery enabled:\t", cfg.LocalAnnEnabled, "\t(localannenabled)")
-	fmt.Fprintln(writer, "Local discovery port:\t", cfg.LocalAnnPort, "\t(localannport)")
-
-	fmt.Fprintln(writer, "Outgoing rate limit in KiB/s:\t", cfg.MaxSendKbps, "\t(maxsend)")
-	fmt.Fprintln(writer, "Incoming rate limit in KiB/s:\t", cfg.MaxRecvKbps, "\t(maxrecv)")
-	fmt.Fprintln(writer, "Reconnect interval in seconds:\t", cfg.ReconnectIntervalS, "\t(reconnect)")
-	fmt.Fprintln(writer, "Start browser:\t", cfg.StartBrowser, "\t(browser)")
-	fmt.Fprintln(writer, "Enable UPnP:\t", cfg.NATEnabled, "\t(nat)")
-	fmt.Fprintln(writer, "UPnP Lease in minutes:\t", cfg.NATLeaseM, "\t(natlease)")
-	fmt.Fprintln(writer, "UPnP Renewal period in minutes:\t", cfg.NATRenewalM, "\t(natrenew)")
-	fmt.Fprintln(writer, "Restart on Wake Up:\t", cfg.RestartOnWakeup, "\t(wake)")
-
-	reporting := "unrecognized value"
-	switch cfg.URAccepted {
-	case -1:
-		reporting = "false"
-	case 0:
-		reporting = "undecided/false"
-	case 1:
-		reporting = "true"
-	}
-	fmt.Fprintln(writer, "Anonymous usage reporting:\t", reporting, "\t(reporting)")
-
-	writer.Flush()
-}
-
-func optionsGet(c *cli.Context) {
-	cfg := getConfig(c).Options
-	arg := c.Args()[0]
-	switch strings.ToLower(arg) {
-	case "address":
-		fmt.Println(strings.Join(cfg.ListenAddresses, "\n"))
-	case "globalannenabled":
-		fmt.Println(cfg.GlobalAnnEnabled)
-	case "globalannservers":
-		fmt.Println(strings.Join(cfg.GlobalAnnServers, "\n"))
-	case "localannenabled":
-		fmt.Println(cfg.LocalAnnEnabled)
-	case "localannport":
-		fmt.Println(cfg.LocalAnnPort)
-	case "maxsend":
-		fmt.Println(cfg.MaxSendKbps)
-	case "maxrecv":
-		fmt.Println(cfg.MaxRecvKbps)
-	case "reconnect":
-		fmt.Println(cfg.ReconnectIntervalS)
-	case "browser":
-		fmt.Println(cfg.StartBrowser)
-	case "nat":
-		fmt.Println(cfg.NATEnabled)
-	case "natlease":
-		fmt.Println(cfg.NATLeaseM)
-	case "natrenew":
-		fmt.Println(cfg.NATRenewalM)
-	case "reporting":
-		switch cfg.URAccepted {
-		case -1:
-			fmt.Println("false")
-		case 0:
-			fmt.Println("undecided/false")
-		case 1:
-			fmt.Println("true")
-		default:
-			fmt.Println("unknown")
-		}
-	case "wake":
-		fmt.Println(cfg.RestartOnWakeup)
-	default:
-		die("Invalid setting: " + arg + "\nAvailable settings: address, globalannenabled, globalannserver, localannenabled, localannport, maxsend, maxrecv, reconnect, browser, upnp, upnplease, upnprenew, reporting, wake")
-	}
-}
-
-func optionsSet(c *cli.Context) {
-	config := getConfig(c)
-	arg := c.Args()[0]
-	val := c.Args()[1]
-	switch strings.ToLower(arg) {
-	case "address":
-		for _, item := range c.Args().Tail() {
-			validAddress(item)
-		}
-		config.Options.ListenAddresses = c.Args().Tail()
-	case "globalannenabled":
-		config.Options.GlobalAnnEnabled = parseBool(val)
-	case "globalannserver":
-		for _, item := range c.Args().Tail() {
-			validAddress(item)
-		}
-		config.Options.GlobalAnnServers = c.Args().Tail()
-	case "localannenabled":
-		config.Options.LocalAnnEnabled = parseBool(val)
-	case "localannport":
-		config.Options.LocalAnnPort = parsePort(val)
-	case "maxsend":
-		config.Options.MaxSendKbps = parseUint(val)
-	case "maxrecv":
-		config.Options.MaxRecvKbps = parseUint(val)
-	case "reconnect":
-		config.Options.ReconnectIntervalS = parseUint(val)
-	case "browser":
-		config.Options.StartBrowser = parseBool(val)
-	case "nat":
-		config.Options.NATEnabled = parseBool(val)
-	case "natlease":
-		config.Options.NATLeaseM = parseUint(val)
-	case "natrenew":
-		config.Options.NATRenewalM = parseUint(val)
-	case "reporting":
-		switch strings.ToLower(val) {
-		case "u", "undecided", "unset":
-			config.Options.URAccepted = 0
-		default:
-			boolvalue := parseBool(val)
-			if boolvalue {
-				config.Options.URAccepted = 1
-			} else {
-				config.Options.URAccepted = -1
-			}
-		}
-	case "wake":
-		config.Options.RestartOnWakeup = parseBool(val)
-	default:
-		die("Invalid setting: " + arg + "\nAvailable settings: address, globalannenabled, globalannserver, localannenabled, localannport, maxsend, maxrecv, reconnect, browser, upnp, upnplease, upnprenew, reporting, wake")
-	}
-	setConfig(c, config)
-}
--- a/cmd/stcli/cmd_report.go
+++ b/cmd/stcli/cmd_report.go
@@ -1,72 +0,0 @@
-// Copyright (C) 2014 Audrius Butkevičius
-
-package main
-
-import (
-	"encoding/json"
-	"fmt"
-
-	"github.com/AudriusButkevicius/cli"
-)
-
-func init() {
-	cliCommands = append(cliCommands, cli.Command{
-		Name:     "report",
-		HideHelp: true,
-		Usage:    "Reporting command group",
-		Subcommands: []cli.Command{
-			{
-				Name:     "system",
-				Usage:    "Report system state",
-				Requires: &cli.Requires{},
-				Action:   reportSystem,
-			},
-			{
-				Name:     "connections",
-				Usage:    "Report about connections to other devices",
-				Requires: &cli.Requires{},
-				Action:   reportConnections,
-			},
-			{
-				Name:     "usage",
-				Usage:    "Usage report",
-				Requires: &cli.Requires{},
-				Action:   reportUsage,
-			},
-		},
-	})
-}
-
-func reportSystem(c *cli.Context) {
-	response := httpGet(c, "system/status")
-	data := make(map[string]interface{})
-	json.Unmarshal(responseToBArray(response), &data)
-	prettyPrintJSON(data)
-}
-
-func reportConnections(c *cli.Context) {
-	response := httpGet(c, "system/connections")
-	data := make(map[string]map[string]interface{})
-	json.Unmarshal(responseToBArray(response), &data)
-	var overall map[string]interface{}
-	for key, value := range data {
-		if key == "total" {
-			overall = value
-			continue
-		}
-		value["Device ID"] = key
-		prettyPrintJSON(value)
-		fmt.Println()
-	}
-	if overall != nil {
-		fmt.Println("=== Overall statistics ===")
-		prettyPrintJSON(overall)
-	}
-}
-
-func reportUsage(c *cli.Context) {
-	response := httpGet(c, "svc/report")
-	report := make(map[string]interface{})
-	json.Unmarshal(responseToBArray(response), &report)
-	prettyPrintJSON(report)
-}
--- a/cmd/stcli/errors.go
+++ b/cmd/stcli/errors.go
@@ -0,0 +1,60 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/urfave/cli"
+)
+
+var errorsCommand = cli.Command{
+	Name:     "errors",
+	HideHelp: true,
+	Usage:    "Error command group",
+	Subcommands: []cli.Command{
+		{
+			Name:   "show",
+			Usage:  "Show pending errors",
+			Action: expects(0, dumpOutput("system/error")),
+		},
+		{
+			Name:      "push",
+			Usage:     "Push an error to active clients",
+			ArgsUsage: "[error message]",
+			Action:    expects(1, errorsPush),
+		},
+		{
+			Name:   "clear",
+			Usage:  "Clear pending errors",
+			Action: expects(0, emptyPost("system/error/clear")),
+		},
+	},
+}
+
+func errorsPush(c *cli.Context) error {
+	client := c.App.Metadata["client"].(*APIClient)
+	errStr := strings.Join(c.Args(), " ")
+	response, err := client.Post("system/error", strings.TrimSpace(errStr))
+	if err != nil {
+		return err
+	}
+	if response.StatusCode != 200 {
+		errStr = fmt.Sprint("Failed to push error\nStatus code: ", response.StatusCode)
+		bytes, err := responseToBArray(response)
+		if err != nil {
+			return err
+		}
+		body := string(bytes)
+		if body != "" {
+			errStr += "\nBody: " + body
+		}
+		return fmt.Errorf(errStr)
+	}
+	return nil
+}
--- a/cmd/stcli/labels.go
+++ b/cmd/stcli/labels.go
@@ -1,31 +0,0 @@
-// Copyright (C) 2014 Audrius Butkevičius
-
-package main
-
-var jsonAttributeLabels = map[string]string{
-	"folderMaxMiB":   "Largest folder size in MiB",
-	"folderMaxFiles": "Largest folder file count",
-	"longVersion":    "Long version",
-	"totMiB":         "Total size in MiB",
-	"totFiles":       "Total files",
-	"uniqueID":       "Unique ID",
-	"numFolders":     "Folder count",
-	"numDevices":     "Device count",
-	"memoryUsageMiB": "Memory usage in MiB",
-	"memorySize":     "Total memory in MiB",
-	"sha256Perf":     "SHA256 Benchmark",
-	"At":             "Last contacted",
-	"Completion":     "Percent complete",
-	"InBytesTotal":   "Total bytes received",
-	"OutBytesTotal":  "Total bytes sent",
-	"ClientVersion":  "Client version",
-	"alloc":          "Memory allocated in bytes",
-	"sys":            "Memory using in bytes",
-	"cpuPercent":     "CPU load in percent",
-	"extAnnounceOK":  "External announcments working",
-	"goroutines":     "Number of Go routines",
-	"myID":           "Client ID",
-	"tilde":          "Tilde expands to",
-	"arch":           "Architecture",
-	"os":             "OS",
-}
--- a/cmd/stcli/main.go
+++ b/cmd/stcli/main.go
@@ -1,63 +1,192 @@
-// Copyright (C) 2014 Audrius Butkevičius
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.

 package main

 import (
-	"sort"
+	"bufio"
+	"crypto/tls"
+	"encoding/json"
+	"flag"
+	"log"
+	"os"
+	"reflect"

-	"github.com/AudriusButkevicius/cli"
+	"github.com/AudriusButkevicius/recli"
+	"github.com/flynn-archive/go-shlex"
+	"github.com/mattn/go-isatty"
+	"github.com/pkg/errors"
+	"github.com/syncthing/syncthing/lib/build"
+	"github.com/syncthing/syncthing/lib/config"
+	"github.com/syncthing/syncthing/lib/events"
+	"github.com/syncthing/syncthing/lib/locations"
+	"github.com/syncthing/syncthing/lib/protocol"
+	"github.com/urfave/cli"
 )

-type ByAlphabet []cli.Command
-
-func (a ByAlphabet) Len() int           { return len(a) }
-func (a ByAlphabet) Swap(i, j int)      { a[i], a[j] = a[j], a[i] }
-func (a ByAlphabet) Less(i, j int) bool { return a[i].Name < a[j].Name }
-
-var cliCommands []cli.Command
-
 func main() {
-	app := cli.NewApp()
-	app.Name = "syncthing-cli"
-	app.Author = "Audrius Butkevičius"
-	app.Email = "audrius.butkevicius@gmail.com"
-	app.Usage = "Syncthing command line interface"
-	app.Version = "0.1"
-	app.HideHelp = true
+	// This is somewhat a hack around a chicken and egg problem.
+	// We need to set the home directory and potentially other flags to know where the syncthing instance is running
+	// in order to get it's config ... which we then use to construct the actual CLI ... at which point it's too late
+	// to add flags there...
+	homeBaseDir := locations.GetBaseDir(locations.ConfigBaseDir)
+	guiCfg := config.GUIConfiguration{}

-	app.Flags = []cli.Flag{
+	flags := flag.NewFlagSet("", flag.ContinueOnError)
+	flags.StringVar(&guiCfg.RawAddress, "gui-address", guiCfg.RawAddress, "Override GUI address (e.g. \"http://192.0.2.42:8443\")")
+	flags.StringVar(&guiCfg.APIKey, "gui-apikey", guiCfg.APIKey, "Override GUI API key")
+	flags.StringVar(&homeBaseDir, "home", homeBaseDir, "Set configuration directory")
+
+	// Implement the same flags at the lower CLI, with the same default values (pre-parse), but do nothing with them.
+	// This is so that we could reuse os.Args
+	fakeFlags := []cli.Flag{
 		cli.StringFlag{
-			Name:   "endpoint, e",
-			Value:  "http://127.0.0.1:8384",
-			Usage:  "End point to connect to",
-			EnvVar: "STENDPOINT",
+			Name:  "gui-address",
+			Value: guiCfg.RawAddress,
+			Usage: "Override GUI address (e.g. \"http://192.0.2.42:8443\")",
 		},
 		cli.StringFlag{
-			Name:   "apikey, k",
-			Value:  "",
-			Usage:  "API Key",
-			EnvVar: "STAPIKEY",
+			Name:  "gui-apikey",
+			Value: guiCfg.APIKey,
+			Usage: "Override GUI API key",
 		},
 		cli.StringFlag{
-			Name:   "username, u",
-			Value:  "",
-			Usage:  "Username",
-			EnvVar: "STUSERNAME",
-		},
-		cli.StringFlag{
-			Name:   "password, p",
-			Value:  "",
-			Usage:  "Password",
-			EnvVar: "STPASSWORD",
-		},
-		cli.BoolFlag{
-			Name:   "insecure, i",
-			Usage:  "Do not verify SSL certificate",
-			EnvVar: "STINSECURE",
+			Name:  "home",
+			Value: homeBaseDir,
+			Usage: "Set configuration directory",
 		},
 	}

-	sort.Sort(ByAlphabet(cliCommands))
-	app.Commands = cliCommands
-	app.RunAndExitOnError()
+	// Do not print usage of these flags, and ignore errors as this can't understand plenty of things
+	flags.Usage = func() {}
+	_ = flags.Parse(os.Args[1:])
+
+	// Now if the API key and address is not provided (we are not connecting to a remote instance),
+	// try to rip it out of the config.
+	if guiCfg.RawAddress == "" && guiCfg.APIKey == "" {
+		// Update the base directory
+		err := locations.SetBaseDir(locations.ConfigBaseDir, homeBaseDir)
+		if err != nil {
+			log.Fatal(errors.Wrap(err, "setting home"))
+		}
+
+		// Load the certs and get the ID
+		cert, err := tls.LoadX509KeyPair(
+			locations.Get(locations.CertFile),
+			locations.Get(locations.KeyFile),
+		)
+		if err != nil {
+			log.Fatal(errors.Wrap(err, "reading device ID"))
+		}
+
+		myID := protocol.NewDeviceID(cert.Certificate[0])
+
+		// Load the config
+		cfg, err := config.Load(locations.Get(locations.ConfigFile), myID, events.NoopLogger)
+		if err != nil {
+			log.Fatalln(errors.Wrap(err, "loading config"))
+		}
+
+		guiCfg = cfg.GUI()
+	} else if guiCfg.Address() == "" || guiCfg.APIKey == "" {
+		log.Fatalln("Both -gui-address and -gui-apikey should be specified")
+	}
+
+	if guiCfg.Address() == "" {
+		log.Fatalln("Could not find GUI Address")
+	}
+
+	if guiCfg.APIKey == "" {
+		log.Fatalln("Could not find GUI API key")
+	}
+
+	client := getClient(guiCfg)
+
+	cfg, err := getConfig(client)
+	original := cfg.Copy()
+	if err != nil {
+		log.Fatalln(errors.Wrap(err, "getting config"))
+	}
+
+	// Copy the config and set the default flags
+	recliCfg := recli.DefaultConfig
+	recliCfg.IDTag.Name = "xml"
+	recliCfg.SkipTag.Name = "json"
+
+	commands, err := recli.New(recliCfg).Construct(&cfg)
+	if err != nil {
+		log.Fatalln(errors.Wrap(err, "config reflect"))
+	}
+
+	// Construct the actual CLI
+	app := cli.NewApp()
+	app.Name = "stcli"
+	app.HelpName = app.Name
+	app.Author = "The Syncthing Authors"
+	app.Usage = "Syncthing command line interface"
+	app.Version = build.Version
+	app.Flags = fakeFlags
+	app.Metadata = map[string]interface{}{
+		"client": client,
+	}
+	app.Commands = []cli.Command{
+		{
+			Name:        "config",
+			HideHelp:    true,
+			Usage:       "Configuration modification command group",
+			Subcommands: commands,
+		},
+		showCommand,
+		operationCommand,
+		errorsCommand,
+	}
+
+	tty := isatty.IsTerminal(os.Stdin.Fd()) || isatty.IsCygwinTerminal(os.Stdin.Fd())
+	if !tty {
+		// Not a TTY, consume from stdin
+		scanner := bufio.NewScanner(os.Stdin)
+		for scanner.Scan() {
+			input, err := shlex.Split(scanner.Text())
+			if err != nil {
+				log.Fatalln(errors.Wrap(err, "parsing input"))
+			}
+			if len(input) == 0 {
+				continue
+			}
+			err = app.Run(append(os.Args, input...))
+			if err != nil {
+				log.Fatalln(err)
+			}
+		}
+		err = scanner.Err()
+		if err != nil {
+			log.Fatalln(err)
+		}
+	} else {
+		err = app.Run(os.Args)
+		if err != nil {
+			log.Fatalln(err)
+		}
+	}
+
+	if !reflect.DeepEqual(cfg, original) {
+		body, err := json.MarshalIndent(cfg, "", "  ")
+		if err != nil {
+			log.Fatalln(err)
+		}
+		resp, err := client.Post("system/config", string(body))
+		if err != nil {
+			log.Fatalln(err)
+		}
+		if resp.StatusCode != 200 {
+			body, err := responseToBArray(resp)
+			if err != nil {
+				log.Fatalln(err)
+			}
+			log.Fatalln(string(body))
+		}
+	}
 }
--- a/cmd/stcli/operations.go
+++ b/cmd/stcli/operations.go
@@ -0,0 +1,78 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"fmt"
+
+	"github.com/urfave/cli"
+)
+
+var operationCommand = cli.Command{
+	Name:     "operations",
+	HideHelp: true,
+	Usage:    "Operation command group",
+	Subcommands: []cli.Command{
+		{
+			Name:   "restart",
+			Usage:  "Restart syncthing",
+			Action: expects(0, emptyPost("system/restart")),
+		},
+		{
+			Name:   "shutdown",
+			Usage:  "Shutdown syncthing",
+			Action: expects(0, emptyPost("system/shutdown")),
+		},
+		{
+			Name:   "reset",
+			Usage:  "Reset syncthing deleting all folders and devices",
+			Action: expects(0, emptyPost("system/reset")),
+		},
+		{
+			Name:   "upgrade",
+			Usage:  "Upgrade syncthing (if a newer version is available)",
+			Action: expects(0, emptyPost("system/upgrade")),
+		},
+		{
+			Name:      "folder-override",
+			Usage:     "Override changes on folder (remote for sendonly, local for receiveonly)",
+			ArgsUsage: "[folder id]",
+			Action:    expects(1, foldersOverride),
+		},
+	},
+}
+
+func foldersOverride(c *cli.Context) error {
+	client := c.App.Metadata["client"].(*APIClient)
+	cfg, err := getConfig(client)
+	if err != nil {
+		return err
+	}
+	rid := c.Args()[0]
+	for _, folder := range cfg.Folders {
+		if folder.ID == rid {
+			response, err := client.Post("db/override", "")
+			if err != nil {
+				return err
+			}
+			if response.StatusCode != 200 {
+				errStr := fmt.Sprint("Failed to override changes\nStatus code: ", response.StatusCode)
+				bytes, err := responseToBArray(response)
+				if err != nil {
+					return err
+				}
+				body := string(bytes)
+				if body != "" {
+					errStr += "\nBody: " + body
+				}
+				return fmt.Errorf(errStr)
+			}
+			return nil
+		}
+	}
+	return fmt.Errorf("Folder " + rid + " not found")
+}
--- a/cmd/stcli/show.go
+++ b/cmd/stcli/show.go
@@ -0,0 +1,44 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"github.com/urfave/cli"
+)
+
+var showCommand = cli.Command{
+	Name:     "show",
+	HideHelp: true,
+	Usage:    "Show command group",
+	Subcommands: []cli.Command{
+		{
+			Name:   "version",
+			Usage:  "Show syncthing client version",
+			Action: expects(0, dumpOutput("system/version")),
+		},
+		{
+			Name:   "config-status",
+			Usage:  "Show configuration status, whether or not a restart is required for changes to take effect",
+			Action: expects(0, dumpOutput("system/config/insync")),
+		},
+		{
+			Name:   "system",
+			Usage:  "Show system status",
+			Action: expects(0, dumpOutput("system/status")),
+		},
+		{
+			Name:   "connections",
+			Usage:  "Report about connections to other devices",
+			Action: expects(0, dumpOutput("system/connections")),
+		},
+		{
+			Name:   "usage",
+			Usage:  "Show usage report",
+			Action: expects(0, dumpOutput("svc/report")),
+		},
+	},
+}
--- a/cmd/stcli/utils.go
+++ b/cmd/stcli/utils.go
@@ -1,4 +1,8 @@
-// Copyright (C) 2014 Audrius Butkevičius
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.

 package main

@@ -8,158 +12,83 @@ import (
 	"io/ioutil"
 	"net/http"
 	"os"
-	"regexp"
-	"sort"
-	"strconv"
-	"strings"
-	"text/tabwriter"
-	"unicode"

-	"github.com/AudriusButkevicius/cli"
 	"github.com/syncthing/syncthing/lib/config"
-	"github.com/syncthing/syncthing/lib/protocol"
+	"github.com/urfave/cli"
 )

-func responseToBArray(response *http.Response) []byte {
-	defer response.Body.Close()
+func responseToBArray(response *http.Response) ([]byte, error) {
 	bytes, err := ioutil.ReadAll(response.Body)
 	if err != nil {
-		die(err)
+		return nil, err
 	}
-	return bytes
+	return bytes, response.Body.Close()
 }

-func die(vals ...interface{}) {
-	if len(vals) > 1 || vals[0] != nil {
-		os.Stderr.WriteString(fmt.Sprintln(vals...))
-		os.Exit(1)
+func emptyPost(url string) cli.ActionFunc {
+	return func(c *cli.Context) error {
+		client := c.App.Metadata["client"].(*APIClient)
+		_, err := client.Post(url, "")
+		return err
 	}
 }

-func wrappedHTTPPost(url string) func(c *cli.Context) {
-	return func(c *cli.Context) {
-		httpPost(c, url, "")
-	}
-}
-
-func prettyPrintJSON(json map[string]interface{}) {
-	writer := newTableWriter()
-	remap := make(map[string]interface{})
-	for k, v := range json {
-		key, ok := jsonAttributeLabels[k]
-		if !ok {
-			key = firstUpper(k)
+func dumpOutput(url string) cli.ActionFunc {
+	return func(c *cli.Context) error {
+		client := c.App.Metadata["client"].(*APIClient)
+		response, err := client.Get(url)
+		if err != nil {
+			return err
 		}
-		remap[key] = v
+		return prettyPrintResponse(c, response)
 	}
+}

-	jsonKeys := make([]string, 0, len(remap))
-	for key := range remap {
-		jsonKeys = append(jsonKeys, key)
+func getConfig(c *APIClient) (config.Configuration, error) {
+	cfg := config.Configuration{}
+	response, err := c.Get("system/config")
+	if err != nil {
+		return cfg, err
 	}
-	sort.Strings(jsonKeys)
-	for _, k := range jsonKeys {
-		var value string
-		rvalue := remap[k]
-		switch rvalue.(type) {
-		case int, int16, int32, int64, uint, uint16, uint32, uint64, float32, float64:
-			value = fmt.Sprintf("%.0f", rvalue)
-		default:
-			value = fmt.Sprint(rvalue)
+	bytes, err := responseToBArray(response)
+	if err != nil {
+		return cfg, err
+	}
+	err = json.Unmarshal(bytes, &cfg)
+	if err == nil {
+		return cfg, err
+	}
+	return cfg, nil
+}
+
+func expects(n int, actionFunc cli.ActionFunc) cli.ActionFunc {
+	return func(ctx *cli.Context) error {
+		if ctx.NArg() != n {
+			plural := ""
+			if n != 1 {
+				plural = "s"
+			}
+			return fmt.Errorf("expected %d argument%s, got %d", n, plural, ctx.NArg())
 		}
-		if value == "" {
-			continue
-		}
-		fmt.Fprintln(writer, k+":\t"+value)
-	}
-	writer.Flush()
-}
-
-func firstUpper(str string) string {
-	for i, v := range str {
-		return string(unicode.ToUpper(v)) + str[i+1:]
-	}
-	return ""
-}
-
-func newTableWriter() *tabwriter.Writer {
-	writer := new(tabwriter.Writer)
-	writer.Init(os.Stdout, 0, 8, 0, '\t', 0)
-	return writer
-}
-
-func getMyID(c *cli.Context) string {
-	response := httpGet(c, "system/status")
-	data := make(map[string]interface{})
-	json.Unmarshal(responseToBArray(response), &data)
-	return data["myID"].(string)
-}
-
-func getConfig(c *cli.Context) config.Configuration {
-	response := httpGet(c, "system/config")
-	config := config.Configuration{}
-	json.Unmarshal(responseToBArray(response), &config)
-	return config
-}
-
-func setConfig(c *cli.Context, cfg config.Configuration) {
-	body, err := json.Marshal(cfg)
-	die(err)
-	response := httpPost(c, "system/config", string(body))
-	if response.StatusCode != 200 {
-		die("Unexpected status code", response.StatusCode)
+		return actionFunc(ctx)
 	}
 }

-func parseBool(input string) bool {
-	val, err := strconv.ParseBool(input)
+func prettyPrintJSON(data interface{}) error {
+	enc := json.NewEncoder(os.Stdout)
+	enc.SetIndent("", "  ")
+	return enc.Encode(data)
+}
+
+func prettyPrintResponse(c *cli.Context, response *http.Response) error {
+	bytes, err := responseToBArray(response)
 	if err != nil {
-		die(input + " is not a valid value for a boolean")
+		return err
 	}
-	return val
-}
-
-func parseInt(input string) int {
-	val, err := strconv.ParseInt(input, 0, 64)
-	if err != nil {
-		die(input + " is not a valid value for an integer")
-	}
-	return int(val)
-}
-
-func parseUint(input string) int {
-	val, err := strconv.ParseUint(input, 0, 64)
-	if err != nil {
-		die(input + " is not a valid value for an unsigned integer")
-	}
-	return int(val)
-}
-
-func parsePort(input string) int {
-	port := parseUint(input)
-	if port < 1 || port > 65535 {
-		die(input + " is not a valid port\nExpected value between 1 and 65535")
-	}
-	return port
-}
-
-func validAddress(input string) {
-	tokens := strings.Split(input, ":")
-	if len(tokens) != 2 {
-		die(input + " is not a valid value for an address\nExpected format <ip or hostname>:<port>")
-	}
-	matched, err := regexp.MatchString("^[a-zA-Z0-9]+([-a-zA-Z0-9.]+[-a-zA-Z0-9]+)?$", tokens[0])
-	die(err)
-	if !matched {
-		die(input + " is not a valid value for an address\nExpected format <ip or hostname>:<port>")
-	}
-	parsePort(tokens[1])
-}
-
-func parseDeviceID(input string) protocol.DeviceID {
-	device, err := protocol.DeviceIDFromString(input)
-	if err != nil {
-		die(input + " is not a valid device id")
-	}
-	return device
+	var data interface{}
+	if err := json.Unmarshal(bytes, &data); err != nil {
+		return err
+	}
+	// TODO: Check flag for pretty print format
+	return prettyPrintJSON(data)
 }
--- a/cmd/stcrashreceiver/_testdata/panic.log
+++ b/cmd/stcrashreceiver/_testdata/panic.log
--- a/cmd/stcrashreceiver/sentry.go
+++ b/cmd/stcrashreceiver/sentry.go
@@ -0,0 +1,204 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"bytes"
+	"errors"
+	"io/ioutil"
+	"regexp"
+	"strings"
+	"sync"
+
+	raven "github.com/getsentry/raven-go"
+	"github.com/maruel/panicparse/stack"
+)
+
+const reportServer = "https://crash.syncthing.net/report/"
+
+var loader = newGithubSourceCodeLoader()
+
+func init() {
+	raven.SetSourceCodeLoader(loader)
+}
+
+var (
+	clients    = make(map[string]*raven.Client)
+	clientsMut sync.Mutex
+)
+
+func sendReport(dsn, path string, report []byte) error {
+	pkt, err := parseReport(path, report)
+	if err != nil {
+		return err
+	}
+
+	clientsMut.Lock()
+	defer clientsMut.Unlock()
+
+	cli, ok := clients[dsn]
+	if !ok {
+		cli, err = raven.New(dsn)
+		if err != nil {
+			return err
+		}
+		clients[dsn] = cli
+	}
+
+	// The client sets release and such on the packet before sending, in the
+	// misguided idea that it knows this better than than the packet we give
+	// it. So we copy the values from the packet to the client first...
+	cli.SetRelease(pkt.Release)
+	cli.SetEnvironment(pkt.Environment)
+
+	defer cli.Wait()
+	_, errC := cli.Capture(pkt, nil)
+	return <-errC
+}
+
+func parseReport(path string, report []byte) (*raven.Packet, error) {
+	parts := bytes.SplitN(report, []byte("\n"), 2)
+	if len(parts) != 2 {
+		return nil, errors.New("no first line")
+	}
+
+	version, err := parseVersion(string(parts[0]))
+	if err != nil {
+		return nil, err
+	}
+	report = parts[1]
+
+	foundPanic := false
+	var subjectLine []byte
+	for {
+		parts = bytes.SplitN(report, []byte("\n"), 2)
+		if len(parts) != 2 {
+			return nil, errors.New("no panic line found")
+		}
+
+		line := parts[0]
+		report = parts[1]
+
+		if foundPanic {
+			// The previous line was our "Panic at ..." header. We are now
+			// at the beginning of the real panic trace and this is our
+			// subject line.
+			subjectLine = line
+			break
+		} else if bytes.HasPrefix(line, []byte("Panic at")) {
+			foundPanic = true
+		}
+	}
+
+	r := bytes.NewReader(report)
+	ctx, err := stack.ParseDump(r, ioutil.Discard, false)
+	if err != nil {
+		return nil, err
+	}
+
+	// Lock the source code loader to the version we are processing here.
+	if version.commit != "" {
+		// We have a commit hash, so we know exactly which source to use
+		loader.LockWithVersion(version.commit)
+	} else if strings.HasPrefix(version.tag, "v") {
+		// Lets hope the tag is close enough
+		loader.LockWithVersion(version.tag)
+	} else {
+		// Last resort
+		loader.LockWithVersion("master")
+	}
+	defer loader.Unlock()
+
+	var trace raven.Stacktrace
+	for _, gr := range ctx.Goroutines {
+		if gr.First {
+			trace.Frames = make([]*raven.StacktraceFrame, len(gr.Stack.Calls))
+			for i, sc := range gr.Stack.Calls {
+				trace.Frames[len(trace.Frames)-1-i] = raven.NewStacktraceFrame(0, sc.Func.Name(), sc.SrcPath, sc.Line, 3, nil)
+			}
+			break
+		}
+	}
+
+	pkt := &raven.Packet{
+		Message:     string(subjectLine),
+		Platform:    "go",
+		Release:     version.tag,
+		Environment: version.environment(),
+		Tags: raven.Tags{
+			raven.Tag{Key: "version", Value: version.version},
+			raven.Tag{Key: "tag", Value: version.tag},
+			raven.Tag{Key: "codename", Value: version.codename},
+			raven.Tag{Key: "runtime", Value: version.runtime},
+			raven.Tag{Key: "goos", Value: version.goos},
+			raven.Tag{Key: "goarch", Value: version.goarch},
+			raven.Tag{Key: "builder", Value: version.builder},
+		},
+		Extra: raven.Extra{
+			"url": reportServer + path,
+		},
+		Interfaces: []raven.Interface{&trace},
+	}
+	if version.commit != "" {
+		pkt.Tags = append(pkt.Tags, raven.Tag{Key: "commit", Value: version.commit})
+	}
+
+	return pkt, nil
+}
+
+// syncthing v1.1.4-rc.1+30-g6aaae618-dirty-crashrep "Erbium Earthworm" (go1.12.5 darwin-amd64) jb@kvin.kastelo.net 2019-05-23 16:08:14 UTC
+var longVersionRE = regexp.MustCompile(`syncthing\s+(v[^\s]+)\s+"([^"]+)"\s\(([^\s]+)\s+([^-]+)-([^)]+)\)\s+([^\s]+)`)
+
+type version struct {
+	version  string // "v1.1.4-rc.1+30-g6aaae618-dirty-crashrep"
+	tag      string // "v1.1.4-rc.1"
+	commit   string // "6aaae618", blank when absent
+	codename string // "Erbium Earthworm"
+	runtime  string // "go1.12.5"
+	goos     string // "darwin"
+	goarch   string // "amd64"
+	builder  string // "jb@kvin.kastelo.net"
+}
+
+func (v version) environment() string {
+	if v.commit != "" {
+		return "Development"
+	}
+	if strings.Contains(v.tag, "-rc.") {
+		return "Candidate"
+	}
+	if strings.Contains(v.tag, "-") {
+		return "Beta"
+	}
+	return "Stable"
+}
+
+func parseVersion(line string) (version, error) {
+	m := longVersionRE.FindStringSubmatch(line)
+	if len(m) == 0 {
+		return version{}, errors.New("unintelligeble version string")
+	}
+
+	v := version{
+		version:  m[1],
+		codename: m[2],
+		runtime:  m[3],
+		goos:     m[4],
+		goarch:   m[5],
+		builder:  m[6],
+	}
+	parts := strings.Split(v.version, "+")
+	v.tag = parts[0]
+	if len(parts) > 1 {
+		fields := strings.Split(parts[1], "-")
+		if len(fields) >= 2 && strings.HasPrefix(fields[1], "g") {
+			v.commit = fields[1][1:]
+		}
+	}
+
+	return v, nil
+}
--- a/cmd/stcrashreceiver/sentry_test.go
+++ b/cmd/stcrashreceiver/sentry_test.go
@@ -0,0 +1,64 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"fmt"
+	"io/ioutil"
+	"testing"
+)
+
+func TestParseVersion(t *testing.T) {
+	cases := []struct {
+		longVersion string
+		parsed      version
+	}{
+		{
+			longVersion: `syncthing v1.1.4-rc.1+30-g6aaae618-dirty-crashrep "Erbium Earthworm" (go1.12.5 darwin-amd64) jb@kvin.kastelo.net 2019-05-23 16:08:14 UTC`,
+			parsed: version{
+				version:  "v1.1.4-rc.1+30-g6aaae618-dirty-crashrep",
+				tag:      "v1.1.4-rc.1",
+				commit:   "6aaae618",
+				codename: "Erbium Earthworm",
+				runtime:  "go1.12.5",
+				goos:     "darwin",
+				goarch:   "amd64",
+				builder:  "jb@kvin.kastelo.net",
+			},
+		},
+	}
+
+	for _, tc := range cases {
+		v, err := parseVersion(tc.longVersion)
+		if err != nil {
+			t.Error(err)
+			continue
+		}
+		if v != tc.parsed {
+			t.Error(v)
+		}
+	}
+}
+
+func TestParseReport(t *testing.T) {
+	bs, err := ioutil.ReadFile("_testdata/panic.log")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	pkt, err := parseReport("1/2/345", bs)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	bs, err = pkt.JSON()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	fmt.Printf("%s\n", bs)
+}
--- a/cmd/stcrashreceiver/sourcecodeloader.go
+++ b/cmd/stcrashreceiver/sourcecodeloader.go
@@ -0,0 +1,114 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+)
+
+const (
+	urlPrefix   = "https://raw.githubusercontent.com/syncthing/syncthing/"
+	httpTimeout = 10 * time.Second
+)
+
+type githubSourceCodeLoader struct {
+	mut     sync.Mutex
+	version string
+	cache   map[string]map[string][][]byte // version -> file -> lines
+	client  *http.Client
+}
+
+func newGithubSourceCodeLoader() *githubSourceCodeLoader {
+	return &githubSourceCodeLoader{
+		cache:  make(map[string]map[string][][]byte),
+		client: &http.Client{Timeout: httpTimeout},
+	}
+}
+
+func (l *githubSourceCodeLoader) LockWithVersion(version string) {
+	l.mut.Lock()
+	l.version = version
+	if _, ok := l.cache[version]; !ok {
+		l.cache[version] = make(map[string][][]byte)
+	}
+}
+
+func (l *githubSourceCodeLoader) Unlock() {
+	l.mut.Unlock()
+}
+
+func (l *githubSourceCodeLoader) Load(filename string, line, context int) ([][]byte, int) {
+	filename = filepath.ToSlash(filename)
+	lines, ok := l.cache[l.version][filename]
+	if !ok {
+		// Cache whatever we managed to find (or nil if nothing, so we don't try again)
+		defer func() {
+			l.cache[l.version][filename] = lines
+		}()
+
+		knownPrefixes := []string{"/lib/", "/cmd/"}
+		var idx int
+		for _, pref := range knownPrefixes {
+			idx = strings.Index(filename, pref)
+			if idx >= 0 {
+				break
+			}
+		}
+		if idx == -1 {
+			return nil, 0
+		}
+
+		url := urlPrefix + l.version + filename[idx:]
+		resp, err := l.client.Get(url)
+
+		if err != nil || resp.StatusCode != http.StatusOK {
+			fmt.Println("Loading source:", err.Error())
+			return nil, 0
+		}
+		data, err := ioutil.ReadAll(resp.Body)
+		_ = resp.Body.Close()
+		if err != nil {
+			fmt.Println("Loading source:", err.Error())
+			return nil, 0
+		}
+		lines = bytes.Split(data, []byte{'\n'})
+	}
+
+	return getLineFromLines(lines, line, context)
+}
+
+func getLineFromLines(lines [][]byte, line, context int) ([][]byte, int) {
+	if lines == nil {
+		// cached error from ReadFile: return no lines
+		return nil, 0
+	}
+
+	line-- // stack trace lines are 1-indexed
+	start := line - context
+	var idx int
+	if start < 0 {
+		start = 0
+		idx = line
+	} else {
+		idx = context
+	}
+	end := line + context + 1
+	if line >= len(lines) {
+		return nil, 0
+	}
+	if end > len(lines) {
+		end = len(lines)
+	}
+	return lines[start:end], idx
+}
--- a/cmd/stcrashreceiver/stcrashreceiver.go
+++ b/cmd/stcrashreceiver/stcrashreceiver.go
@@ -0,0 +1,160 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+// Command stcrashreceiver is a trivial HTTP server that allows two things:
+//
+// - uploading files (crash reports) named like a SHA256 hash using a PUT request
+// - checking whether such file exists using a HEAD request
+//
+// Typically this should be deployed behind something that manages HTTPS.
+package main
+
+import (
+	"bytes"
+	"compress/gzip"
+	"flag"
+	"io"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"path"
+	"path/filepath"
+	"strings"
+)
+
+const maxRequestSize = 1 << 20 // 1 MiB
+
+func main() {
+	dir := flag.String("dir", ".", "Directory to store reports in")
+	dsn := flag.String("dsn", "", "Sentry DSN")
+	listen := flag.String("listen", ":22039", "HTTP listen address")
+	flag.Parse()
+
+	cr := &crashReceiver{
+		dir: *dir,
+		dsn: *dsn,
+	}
+
+	log.SetOutput(os.Stdout)
+	if err := http.ListenAndServe(*listen, cr); err != nil {
+		log.Fatalln("HTTP serve:", err)
+	}
+}
+
+type crashReceiver struct {
+	dir string
+	dsn string
+}
+
+func (r *crashReceiver) ServeHTTP(w http.ResponseWriter, req *http.Request) {
+	// The final path component should be a SHA256 hash in hex, so 64 hex
+	// characters. We don't care about case on the request but use lower
+	// case internally.
+	reportID := strings.ToLower(path.Base(req.URL.Path))
+	if len(reportID) != 64 {
+		http.Error(w, "Bad request", http.StatusBadRequest)
+		return
+	}
+	for _, c := range reportID {
+		if c >= 'a' && c <= 'f' {
+			continue
+		}
+		if c >= '0' && c <= '9' {
+			continue
+		}
+		http.Error(w, "Bad request", http.StatusBadRequest)
+		return
+	}
+
+	// The location of the report on disk, compressed
+	fullPath := filepath.Join(r.dir, r.dirFor(reportID), reportID) + ".gz"
+
+	switch req.Method {
+	case http.MethodGet:
+		r.serveGet(fullPath, w, req)
+	case http.MethodHead:
+		r.serveHead(fullPath, w, req)
+	case http.MethodPut:
+		r.servePut(reportID, fullPath, w, req)
+	default:
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+
+// serveGet responds to GET requests by serving the uncompressed report.
+func (r *crashReceiver) serveGet(fullPath string, w http.ResponseWriter, _ *http.Request) {
+	fd, err := os.Open(fullPath)
+	if err != nil {
+		http.Error(w, "Not found", http.StatusNotFound)
+		return
+	}
+
+	defer fd.Close()
+	gr, err := gzip.NewReader(fd)
+	if err != nil {
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+		return
+	}
+	_, _ = io.Copy(w, gr) // best effort
+}
+
+// serveHead responds to HEAD requests by checking if the named report
+// already exists in the system.
+func (r *crashReceiver) serveHead(fullPath string, w http.ResponseWriter, _ *http.Request) {
+	if _, err := os.Lstat(fullPath); err != nil {
+		http.Error(w, "Not found", http.StatusNotFound)
+	}
+}
+
+// servePut accepts and stores the given report.
+func (r *crashReceiver) servePut(reportID, fullPath string, w http.ResponseWriter, req *http.Request) {
+	// Ensure the destination directory exists
+	if err := os.MkdirAll(filepath.Dir(fullPath), 0755); err != nil {
+		log.Println("Creating directory:", err)
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+		return
+	}
+
+	// Read at most maxRequestSize of report data.
+	log.Println("Receiving report", reportID)
+	lr := io.LimitReader(req.Body, maxRequestSize)
+	bs, err := ioutil.ReadAll(lr)
+	if err != nil {
+		log.Println("Reading report:", err)
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+		return
+	}
+
+	// Compress the report for storage
+	buf := new(bytes.Buffer)
+	gw := gzip.NewWriter(buf)
+	_, _ = gw.Write(bs) // can't fail
+	gw.Close()
+
+	// Create an output file with the compressed report
+	err = ioutil.WriteFile(fullPath, buf.Bytes(), 0644)
+	if err != nil {
+		log.Println("Saving report:", err)
+		http.Error(w, "Internal server error", http.StatusInternalServerError)
+		return
+	}
+
+	// Send the report to Sentry
+	if r.dsn != "" {
+		go func() {
+			// There's no need for the client to have to wait for this part.
+			if err := sendReport(r.dsn, reportID, bs); err != nil {
+				log.Println("Failed to send report:", err)
+			}
+		}()
+	}
+}
+
+// 01234567890abcdef... => 01/23
+func (r *crashReceiver) dirFor(base string) string {
+	return filepath.Join(base[0:2], base[2:4])
+}
--- a/cmd/stdiscosrv/apisrv.go
+++ b/cmd/stdiscosrv/apisrv.go
@@ -8,6 +8,7 @@ package main

 import (
 	"bytes"
+	"context"
 	"crypto/tls"
 	"encoding/json"
 	"encoding/pem"
@@ -17,12 +18,13 @@ import (
 	"net"
 	"net/http"
 	"net/url"
+	"sort"
 	"strconv"
+	"strings"
 	"sync"
 	"time"

 	"github.com/syncthing/syncthing/lib/protocol"
-	"golang.org/x/net/context"
 )

 // announcement is the format received from and sent to clients
@@ -194,6 +196,7 @@ func (s *apiSrv) handleGET(ctx context.Context, w http.ResponseWriter, req *http

 		if misses%notFoundMissesWriteInterval == 0 {
 			rec.Misses = misses
+			rec.Missed = time.Now().UnixNano()
 			rec.Addresses = nil
 			// rec.Seen retained from get
 			s.db.put(key, rec)
@@ -277,6 +280,10 @@ func (s *apiSrv) handleAnnounce(remote net.IP, deviceID protocol.DeviceID, addre
 		dbAddrs[i].Expires = expire
 	}

+	// The address slice must always be sorted for database merges to work
+	// properly.
+	sort.Sort(databaseAddressOrder(dbAddrs))
+
 	seen := now.UnixNano()
 	if s.repl != nil {
 		s.repl.send(key, dbAddrs, seen)
@@ -293,28 +300,66 @@ func certificateBytes(req *http.Request) []byte {
 		return req.TLS.PeerCertificates[0].Raw
 	}

+	var bs []byte
+
 	if hdr := req.Header.Get("X-SSL-Cert"); hdr != "" {
-		bs := []byte(hdr)
-		// The certificate is in PEM format but with spaces for newlines. We
-		// need to reinstate the newlines for the PEM decoder. But we need to
-		// leave the spaces in the BEGIN and END lines - the first and last
-		// space - alone.
-		firstSpace := bytes.Index(bs, []byte(" "))
-		lastSpace := bytes.LastIndex(bs, []byte(" "))
-		for i := firstSpace + 1; i < lastSpace; i++ {
-			if bs[i] == ' ' {
-				bs[i] = '\n'
+		if strings.Contains(hdr, "%") {
+			// Nginx using $ssl_client_escaped_cert
+			// The certificate is in PEM format with url encoding.
+			// We need to decode for the PEM decoder
+			hdr, err := url.QueryUnescape(hdr)
+			if err != nil {
+				// Decoding failed
+				return nil
+			}
+
+			bs = []byte(hdr)
+		} else {
+			// Nginx using $ssl_client_cert
+			// The certificate is in PEM format but with spaces for newlines. We
+			// need to reinstate the newlines for the PEM decoder. But we need to
+			// leave the spaces in the BEGIN and END lines - the first and last
+			// space - alone.
+			bs = []byte(hdr)
+			firstSpace := bytes.Index(bs, []byte(" "))
+			lastSpace := bytes.LastIndex(bs, []byte(" "))
+			for i := firstSpace + 1; i < lastSpace; i++ {
+				if bs[i] == ' ' {
+					bs[i] = '\n'
+				}
 			}
 		}
-		block, _ := pem.Decode(bs)
-		if block == nil {
+	} else if hdr := req.Header.Get("X-Forwarded-Tls-Client-Cert"); hdr != "" {
+		// Traefik 2 passtlsclientcert
+		// The certificate is in PEM format with url encoding but without newlines
+		// and start/end statements. We need to decode, reinstate the newlines every 64
+		// character and add statements for the PEM decoder
+		hdr, err := url.QueryUnescape(hdr)
+		if err != nil {
 			// Decoding failed
 			return nil
 		}
-		return block.Bytes
+
+		for i := 64; i < len(hdr); i += 65 {
+			hdr = hdr[:i] + "\n" + hdr[i:]
+		}
+
+		hdr = "-----BEGIN CERTIFICATE-----\n" + hdr
+		hdr = hdr + "\n-----END CERTIFICATE-----\n"
+		bs = []byte(hdr)
 	}

-	return nil
+	if bs == nil {
+		return nil
+	}
+
+	block, _ := pem.Decode(bs)
+	if block == nil {
+		// Decoding failed
+		return nil
+	}
+
+	return block.Bytes
 }

 // fixupAddresses checks the list of addresses, removing invalid ones and
@@ -333,14 +378,29 @@ func fixupAddresses(remote net.IP, addresses []string) []string {
 		}

 		ip := net.ParseIP(host)
+
+		// Some classes of IP are no-go.
+		if ip.IsLoopback() || ip.IsMulticast() {
+			continue
+		}
+
 		if host == "" || ip.IsUnspecified() {
-			// Do not use IPv6 remote address if requested scheme is tcp4
-			if uri.Scheme == "tcp4" && remote.To4() == nil {
+			// Replace the unspecified IP with the request source.
+
+			// ... unless the request source is the loopback address or
+			// multicast/unspecified (can't happen, really).
+			if remote.IsLoopback() || remote.IsMulticast() || remote.IsUnspecified() {
 				continue
 			}

-			// Do not use IPv4 remote address if requested scheme is tcp6
-			if uri.Scheme == "tcp6" && remote.To4() != nil {
+			// Do not use IPv6 remote address if requested scheme is ...4
+			// (i.e., tcp4, etc.)
+			if strings.HasSuffix(uri.Scheme, "4") && remote.To4() == nil {
+				continue
+			}
+
+			// Do not use IPv4 remote address if requested scheme is ...6
+			if strings.HasSuffix(uri.Scheme, "6") && remote.To4() != nil {
 				continue
 			}

--- a/cmd/stdiscosrv/apisrv_test.go
+++ b/cmd/stdiscosrv/apisrv_test.go
@@ -0,0 +1,65 @@
+// Copyright (C) 2018 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"fmt"
+	"net"
+	"testing"
+)
+
+func TestFixupAddresses(t *testing.T) {
+	cases := []struct {
+		remote net.IP
+		in     []string
+		out    []string
+	}{
+		{ // verbatim passthrough
+			in:  []string{"tcp://1.2.3.4:22000"},
+			out: []string{"tcp://1.2.3.4:22000"},
+		}, { // unspecified replaced by remote
+			remote: net.ParseIP("1.2.3.4"),
+			in:     []string{"tcp://:22000", "tcp://192.0.2.42:22000"},
+			out:    []string{"tcp://1.2.3.4:22000", "tcp://192.0.2.42:22000"},
+		}, { // unspecified not used as replacement
+			remote: net.ParseIP("0.0.0.0"),
+			in:     []string{"tcp://:22000", "tcp://192.0.2.42:22000"},
+			out:    []string{"tcp://192.0.2.42:22000"},
+		}, { // unspecified not used as replacement
+			remote: net.ParseIP("::"),
+			in:     []string{"tcp://:22000", "tcp://192.0.2.42:22000"},
+			out:    []string{"tcp://192.0.2.42:22000"},
+		}, { // localhost not used as replacement
+			remote: net.ParseIP("127.0.0.1"),
+			in:     []string{"tcp://:22000", "tcp://192.0.2.42:22000"},
+			out:    []string{"tcp://192.0.2.42:22000"},
+		}, { // localhost not used as replacement
+			remote: net.ParseIP("::1"),
+			in:     []string{"tcp://:22000", "tcp://192.0.2.42:22000"},
+			out:    []string{"tcp://192.0.2.42:22000"},
+		}, { // multicast not used as replacement
+			remote: net.ParseIP("224.0.0.1"),
+			in:     []string{"tcp://:22000", "tcp://192.0.2.42:22000"},
+			out:    []string{"tcp://192.0.2.42:22000"},
+		}, { // multicast not used as replacement
+			remote: net.ParseIP("ff80::42"),
+			in:     []string{"tcp://:22000", "tcp://192.0.2.42:22000"},
+			out:    []string{"tcp://192.0.2.42:22000"},
+		}, { // explicitly announced weirdness is also filtered
+			remote: net.ParseIP("192.0.2.42"),
+			in:     []string{"tcp://:22000", "tcp://127.1.2.3:22000", "tcp://[::1]:22000", "tcp://[ff80::42]:22000"},
+			out:    []string{"tcp://192.0.2.42:22000"},
+		},
+	}
+
+	for _, tc := range cases {
+		out := fixupAddresses(tc.remote, tc.in)
+		if fmt.Sprint(out) != fmt.Sprint(tc.out) {
+			t.Errorf("fixupAddresses(%v, %v) => %v, expected %v", tc.remote, tc.in, out, tc.out)
+		}
+	}
+}
--- a/cmd/stdiscosrv/database.go
+++ b/cmd/stdiscosrv/database.go
@@ -5,11 +5,12 @@
 // You can obtain one at https://mozilla.org/MPL/2.0/.

 //go:generate go run ../../script/protofmt.go database.proto
-//go:generate protoc -I ../../../../../ -I ../../vendor/ -I ../../vendor/github.com/gogo/protobuf/protobuf -I . --gogofast_out=. database.proto
+//go:generate protoc -I ../../ -I . --gogofast_out=. database.proto

 package main

 import (
+	"log"
 	"sort"
 	"time"

@@ -162,10 +163,10 @@ func (s *levelDBStore) Serve() {
 	// Start the statistics serve routine. It will exit with us when
 	// statisticsTrigger is closed.
 	statisticsTrigger := make(chan struct{})
-	defer close(statisticsTrigger)
 	statisticsDone := make(chan struct{})
 	go s.statisticsServe(statisticsTrigger, statisticsDone)

+loop:
 	for {
 		select {
 		case fn := <-s.inbox:
@@ -184,17 +185,24 @@ func (s *levelDBStore) Serve() {

 		case <-s.stop:
 			// We're done.
-			return
+			close(statisticsTrigger)
+			break loop
 		}
 	}
+
+	// Also wait for statisticsServe to return
+	<-statisticsDone
 }

 func (s *levelDBStore) statisticsServe(trigger <-chan struct{}, done chan<- struct{}) {
+	defer close(done)
+
 	for range trigger {
 		t0 := time.Now()
 		nowNanos := t0.UnixNano()
 		cutoff24h := t0.Add(-24 * time.Hour).UnixNano()
 		cutoff1w := t0.Add(-7 * 24 * time.Hour).UnixNano()
+		cutoff2Mon := t0.Add(-60 * 24 * time.Hour).UnixNano()
 		current, last24h, last1w, inactive, errors := 0, 0, 0, 0, 0

 		iter := s.db.NewIterator(&util.Range{}, nil)
@@ -217,6 +225,17 @@ func (s *levelDBStore) statisticsServe(trigger <-chan struct{}, done chan<- stru
 				last24h++
 			case rec.Seen > cutoff1w:
 				last1w++
+			case rec.Seen > cutoff2Mon:
+				inactive++
+			case rec.Missed < cutoff2Mon:
+				// It hasn't been seen lately and we haven't recorded
+				// someone asking for this device in a long time either;
+				// delete the record.
+				if err := s.db.Delete(iter.Key(), nil); err != nil {
+					databaseOperations.WithLabelValues(dbOpDelete, dbResError).Inc()
+				} else {
+					databaseOperations.WithLabelValues(dbOpDelete, dbResSuccess).Inc()
+				}
 			default:
 				inactive++
 			}
@@ -245,12 +264,15 @@ func (s *levelDBStore) Stop() {
 // chosen for any duplicates.
 func merge(a, b DatabaseRecord) DatabaseRecord {
 	// Both lists must be sorted for this to work.
-	sort.Slice(a.Addresses, func(i, j int) bool {
-		return a.Addresses[i].Address < a.Addresses[j].Address
-	})
-	sort.Slice(b.Addresses, func(i, j int) bool {
-		return b.Addresses[i].Address < b.Addresses[j].Address
-	})
+	if !sort.IsSorted(databaseAddressOrder(a.Addresses)) {
+		log.Println("Warning: bug: addresses not correctly sorted in merge")
+		a.Addresses = sortedAddressCopy(a.Addresses)
+	}
+	if !sort.IsSorted(databaseAddressOrder(b.Addresses)) {
+		// no warning because this is the side we read from disk and it may
+		// legitimately predate correct sorting.
+		b.Addresses = sortedAddressCopy(b.Addresses)
+	}

 	res := DatabaseRecord{
 		Addresses: make([]DatabaseAddress, 0, len(a.Addresses)+len(b.Addresses)),
@@ -334,3 +356,24 @@ func expire(addrs []DatabaseAddress, now int64) []DatabaseAddress {
 	}
 	return addrs
 }
+
+func sortedAddressCopy(addrs []DatabaseAddress) []DatabaseAddress {
+	sorted := make([]DatabaseAddress, len(addrs))
+	copy(sorted, addrs)
+	sort.Sort(databaseAddressOrder(sorted))
+	return sorted
+}
+
+type databaseAddressOrder []DatabaseAddress
+
+func (s databaseAddressOrder) Less(a, b int) bool {
+	return s[a].Address < s[b].Address
+}
+
+func (s databaseAddressOrder) Swap(a, b int) {
+	s[a], s[b] = s[b], s[a]
+}
+
+func (s databaseAddressOrder) Len() int {
+	return len(s)
+}
--- a/cmd/stdiscosrv/database.pb.go
+++ b/cmd/stdiscosrv/database.pb.go
@@ -1,25 +1,16 @@
 // Code generated by protoc-gen-gogo. DO NOT EDIT.
 // source: database.proto

-/*
-	Package main is a generated protocol buffer package.
-
-	It is generated from these files:
-		database.proto
-
-	It has these top-level messages:
-		DatabaseRecord
-		ReplicationRecord
-		DatabaseAddress
-*/
 package main

-import proto "github.com/gogo/protobuf/proto"
-import fmt "fmt"
-import math "math"
-import _ "github.com/gogo/protobuf/gogoproto"
-
-import io "io"
+import (
+	fmt "fmt"
+	_ "github.com/gogo/protobuf/gogoproto"
+	proto "github.com/gogo/protobuf/proto"
+	io "io"
+	math "math"
+	math_bits "math/bits"
+)

 // Reference imports to suppress errors if they are not otherwise used.
 var _ = proto.Marshal
@@ -30,49 +21,158 @@ var _ = math.Inf
 // is compatible with the proto package it is being compiled against.
 // A compilation error at this line likely means your copy of the
 // proto package needs to be updated.
-const _ = proto.GoGoProtoPackageIsVersion2 // please upgrade the proto package
+const _ = proto.GoGoProtoPackageIsVersion3 // please upgrade the proto package

 type DatabaseRecord struct {
-	Addresses []DatabaseAddress `protobuf:"bytes,1,rep,name=addresses" json:"addresses"`
+	Addresses []DatabaseAddress `protobuf:"bytes,1,rep,name=addresses,proto3" json:"addresses"`
 	Misses    int32             `protobuf:"varint,2,opt,name=misses,proto3" json:"misses,omitempty"`
 	Seen      int64             `protobuf:"varint,3,opt,name=seen,proto3" json:"seen,omitempty"`
+	Missed    int64             `protobuf:"varint,4,opt,name=missed,proto3" json:"missed,omitempty"`
 }

-func (m *DatabaseRecord) Reset()                    { *m = DatabaseRecord{} }
-func (m *DatabaseRecord) String() string            { return proto.CompactTextString(m) }
-func (*DatabaseRecord) ProtoMessage()               {}
-func (*DatabaseRecord) Descriptor() ([]byte, []int) { return fileDescriptorDatabase, []int{0} }
+func (m *DatabaseRecord) Reset()         { *m = DatabaseRecord{} }
+func (m *DatabaseRecord) String() string { return proto.CompactTextString(m) }
+func (*DatabaseRecord) ProtoMessage()    {}
+func (*DatabaseRecord) Descriptor() ([]byte, []int) {
+	return fileDescriptor_b90fe3356ea5df07, []int{0}
+}
+func (m *DatabaseRecord) XXX_Unmarshal(b []byte) error {
+	return m.Unmarshal(b)
+}
+func (m *DatabaseRecord) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	if deterministic {
+		return xxx_messageInfo_DatabaseRecord.Marshal(b, m, deterministic)
+	} else {
+		b = b[:cap(b)]
+		n, err := m.MarshalToSizedBuffer(b)
+		if err != nil {
+			return nil, err
+		}
+		return b[:n], nil
+	}
+}
+func (m *DatabaseRecord) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_DatabaseRecord.Merge(m, src)
+}
+func (m *DatabaseRecord) XXX_Size() int {
+	return m.Size()
+}
+func (m *DatabaseRecord) XXX_DiscardUnknown() {
+	xxx_messageInfo_DatabaseRecord.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_DatabaseRecord proto.InternalMessageInfo

 type ReplicationRecord struct {
 	Key       string            `protobuf:"bytes,1,opt,name=key,proto3" json:"key,omitempty"`
-	Addresses []DatabaseAddress `protobuf:"bytes,2,rep,name=addresses" json:"addresses"`
+	Addresses []DatabaseAddress `protobuf:"bytes,2,rep,name=addresses,proto3" json:"addresses"`
 	Seen      int64             `protobuf:"varint,3,opt,name=seen,proto3" json:"seen,omitempty"`
 }

-func (m *ReplicationRecord) Reset()                    { *m = ReplicationRecord{} }
-func (m *ReplicationRecord) String() string            { return proto.CompactTextString(m) }
-func (*ReplicationRecord) ProtoMessage()               {}
-func (*ReplicationRecord) Descriptor() ([]byte, []int) { return fileDescriptorDatabase, []int{1} }
+func (m *ReplicationRecord) Reset()         { *m = ReplicationRecord{} }
+func (m *ReplicationRecord) String() string { return proto.CompactTextString(m) }
+func (*ReplicationRecord) ProtoMessage()    {}
+func (*ReplicationRecord) Descriptor() ([]byte, []int) {
+	return fileDescriptor_b90fe3356ea5df07, []int{1}
+}
+func (m *ReplicationRecord) XXX_Unmarshal(b []byte) error {
+	return m.Unmarshal(b)
+}
+func (m *ReplicationRecord) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	if deterministic {
+		return xxx_messageInfo_ReplicationRecord.Marshal(b, m, deterministic)
+	} else {
+		b = b[:cap(b)]
+		n, err := m.MarshalToSizedBuffer(b)
+		if err != nil {
+			return nil, err
+		}
+		return b[:n], nil
+	}
+}
+func (m *ReplicationRecord) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_ReplicationRecord.Merge(m, src)
+}
+func (m *ReplicationRecord) XXX_Size() int {
+	return m.Size()
+}
+func (m *ReplicationRecord) XXX_DiscardUnknown() {
+	xxx_messageInfo_ReplicationRecord.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_ReplicationRecord proto.InternalMessageInfo

 type DatabaseAddress struct {
 	Address string `protobuf:"bytes,1,opt,name=address,proto3" json:"address,omitempty"`
 	Expires int64  `protobuf:"varint,2,opt,name=expires,proto3" json:"expires,omitempty"`
 }

-func (m *DatabaseAddress) Reset()                    { *m = DatabaseAddress{} }
-func (m *DatabaseAddress) String() string            { return proto.CompactTextString(m) }
-func (*DatabaseAddress) ProtoMessage()               {}
-func (*DatabaseAddress) Descriptor() ([]byte, []int) { return fileDescriptorDatabase, []int{2} }
+func (m *DatabaseAddress) Reset()         { *m = DatabaseAddress{} }
+func (m *DatabaseAddress) String() string { return proto.CompactTextString(m) }
+func (*DatabaseAddress) ProtoMessage()    {}
+func (*DatabaseAddress) Descriptor() ([]byte, []int) {
+	return fileDescriptor_b90fe3356ea5df07, []int{2}
+}
+func (m *DatabaseAddress) XXX_Unmarshal(b []byte) error {
+	return m.Unmarshal(b)
+}
+func (m *DatabaseAddress) XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {
+	if deterministic {
+		return xxx_messageInfo_DatabaseAddress.Marshal(b, m, deterministic)
+	} else {
+		b = b[:cap(b)]
+		n, err := m.MarshalToSizedBuffer(b)
+		if err != nil {
+			return nil, err
+		}
+		return b[:n], nil
+	}
+}
+func (m *DatabaseAddress) XXX_Merge(src proto.Message) {
+	xxx_messageInfo_DatabaseAddress.Merge(m, src)
+}
+func (m *DatabaseAddress) XXX_Size() int {
+	return m.Size()
+}
+func (m *DatabaseAddress) XXX_DiscardUnknown() {
+	xxx_messageInfo_DatabaseAddress.DiscardUnknown(m)
+}
+
+var xxx_messageInfo_DatabaseAddress proto.InternalMessageInfo

 func init() {
 	proto.RegisterType((*DatabaseRecord)(nil), "main.DatabaseRecord")
 	proto.RegisterType((*ReplicationRecord)(nil), "main.ReplicationRecord")
 	proto.RegisterType((*DatabaseAddress)(nil), "main.DatabaseAddress")
 }
+
+func init() { proto.RegisterFile("database.proto", fileDescriptor_b90fe3356ea5df07) }
+
+var fileDescriptor_b90fe3356ea5df07 = []byte{
+	// 270 bytes of a gzipped FileDescriptorProto
+	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0x94, 0x90, 0x41, 0x4a, 0xc4, 0x30,
+	0x18, 0x85, 0x9b, 0x49, 0x1d, 0x99, 0x08, 0xa3, 0x06, 0x94, 0x20, 0x12, 0x4b, 0xdd, 0x74, 0xd5,
+	0x01, 0x5d, 0xb9, 0x74, 0xd0, 0x0b, 0xe4, 0x06, 0xe9, 0xe4, 0x77, 0x08, 0x3a, 0x4d, 0x49, 0x2a,
+	0xe8, 0x29, 0xf4, 0x58, 0x5d, 0xce, 0xd2, 0x95, 0x68, 0x7b, 0x11, 0x69, 0x26, 0x55, 0x14, 0x37,
+	0xb3, 0x7b, 0xdf, 0xff, 0xbf, 0x97, 0xbc, 0x84, 0x4c, 0x95, 0xac, 0x65, 0x21, 0x1d, 0xe4, 0x95,
+	0x35, 0xb5, 0xa1, 0xf1, 0x4a, 0xea, 0xf2, 0xe4, 0xdc, 0x42, 0x65, 0xdc, 0xcc, 0x8f, 0x8a, 0xc7,
+	0xbb, 0xd9, 0xd2, 0x2c, 0x8d, 0x07, 0xaf, 0x36, 0xd6, 0xf4, 0x05, 0x91, 0xe9, 0x4d, 0x48, 0x0b,
+	0x58, 0x18, 0xab, 0xe8, 0x15, 0x99, 0x48, 0xa5, 0x2c, 0x38, 0x07, 0x8e, 0xa1, 0x04, 0x67, 0x7b,
+	0x17, 0x47, 0x79, 0x7f, 0x62, 0x3e, 0x18, 0xaf, 0x37, 0xeb, 0x79, 0xdc, 0xbc, 0x9f, 0x45, 0xe2,
+	0xc7, 0x4d, 0x8f, 0xc9, 0x78, 0xa5, 0x7d, 0x6e, 0x94, 0xa0, 0x6c, 0x47, 0x04, 0xa2, 0x94, 0xc4,
+	0x0e, 0xa0, 0x64, 0x38, 0x41, 0x19, 0x16, 0x5e, 0x7f, 0x7b, 0x15, 0x8b, 0xfd, 0x34, 0x50, 0x5a,
+	0x93, 0x43, 0x01, 0xd5, 0x83, 0x5e, 0xc8, 0x5a, 0x9b, 0x32, 0x74, 0x3a, 0x20, 0xf8, 0x1e, 0x9e,
+	0x19, 0x4a, 0x50, 0x36, 0x11, 0xbd, 0xfc, 0xdd, 0x72, 0xb4, 0x55, 0xcb, 0x7f, 0xda, 0xa4, 0xb7,
+	0x64, 0xff, 0x4f, 0x8e, 0x32, 0xb2, 0x1b, 0x32, 0xe1, 0xde, 0x01, 0xfb, 0x0d, 0x3c, 0x55, 0xda,
+	0x86, 0x77, 0x62, 0x31, 0xe0, 0xfc, 0xb4, 0xf9, 0xe4, 0x51, 0xd3, 0x72, 0xb4, 0x6e, 0x39, 0xfa,
+	0x68, 0x39, 0x7a, 0xed, 0x78, 0xb4, 0xee, 0x78, 0xf4, 0xd6, 0xf1, 0xa8, 0x18, 0xfb, 0x3f, 0xbf,
+	0xfc, 0x0a, 0x00, 0x00, 0xff, 0xff, 0x7a, 0xa2, 0xf6, 0x1e, 0xb0, 0x01, 0x00, 0x00,
+}
+
 func (m *DatabaseRecord) Marshal() (dAtA []byte, err error) {
 	size := m.Size()
 	dAtA = make([]byte, size)
-	n, err := m.MarshalTo(dAtA)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
 	if err != nil {
 		return nil, err
 	}
@@ -80,39 +180,51 @@ func (m *DatabaseRecord) Marshal() (dAtA []byte, err error) {
 }

 func (m *DatabaseRecord) MarshalTo(dAtA []byte) (int, error) {
-	var i int
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+func (m *DatabaseRecord) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
 	_ = i
 	var l int
 	_ = l
-	if len(m.Addresses) > 0 {
-		for _, msg := range m.Addresses {
-			dAtA[i] = 0xa
-			i++
-			i = encodeVarintDatabase(dAtA, i, uint64(msg.Size()))
-			n, err := msg.MarshalTo(dAtA[i:])
-			if err != nil {
-				return 0, err
-			}
-			i += n
-		}
-	}
-	if m.Misses != 0 {
-		dAtA[i] = 0x10
-		i++
-		i = encodeVarintDatabase(dAtA, i, uint64(m.Misses))
+	if m.Missed != 0 {
+		i = encodeVarintDatabase(dAtA, i, uint64(m.Missed))
+		i--
+		dAtA[i] = 0x20
 	}
 	if m.Seen != 0 {
-		dAtA[i] = 0x18
-		i++
 		i = encodeVarintDatabase(dAtA, i, uint64(m.Seen))
+		i--
+		dAtA[i] = 0x18
 	}
-	return i, nil
+	if m.Misses != 0 {
+		i = encodeVarintDatabase(dAtA, i, uint64(m.Misses))
+		i--
+		dAtA[i] = 0x10
+	}
+	if len(m.Addresses) > 0 {
+		for iNdEx := len(m.Addresses) - 1; iNdEx >= 0; iNdEx-- {
+			{
+				size, err := m.Addresses[iNdEx].MarshalToSizedBuffer(dAtA[:i])
+				if err != nil {
+					return 0, err
+				}
+				i -= size
+				i = encodeVarintDatabase(dAtA, i, uint64(size))
+			}
+			i--
+			dAtA[i] = 0xa
+		}
+	}
+	return len(dAtA) - i, nil
 }

 func (m *ReplicationRecord) Marshal() (dAtA []byte, err error) {
 	size := m.Size()
 	dAtA = make([]byte, size)
-	n, err := m.MarshalTo(dAtA)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
 	if err != nil {
 		return nil, err
 	}
@@ -120,40 +232,48 @@ func (m *ReplicationRecord) Marshal() (dAtA []byte, err error) {
 }

 func (m *ReplicationRecord) MarshalTo(dAtA []byte) (int, error) {
-	var i int
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+func (m *ReplicationRecord) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
 	_ = i
 	var l int
 	_ = l
-	if len(m.Key) > 0 {
-		dAtA[i] = 0xa
-		i++
-		i = encodeVarintDatabase(dAtA, i, uint64(len(m.Key)))
-		i += copy(dAtA[i:], m.Key)
+	if m.Seen != 0 {
+		i = encodeVarintDatabase(dAtA, i, uint64(m.Seen))
+		i--
+		dAtA[i] = 0x18
 	}
 	if len(m.Addresses) > 0 {
-		for _, msg := range m.Addresses {
-			dAtA[i] = 0x12
-			i++
-			i = encodeVarintDatabase(dAtA, i, uint64(msg.Size()))
-			n, err := msg.MarshalTo(dAtA[i:])
-			if err != nil {
-				return 0, err
+		for iNdEx := len(m.Addresses) - 1; iNdEx >= 0; iNdEx-- {
+			{
+				size, err := m.Addresses[iNdEx].MarshalToSizedBuffer(dAtA[:i])
+				if err != nil {
+					return 0, err
+				}
+				i -= size
+				i = encodeVarintDatabase(dAtA, i, uint64(size))
 			}
-			i += n
+			i--
+			dAtA[i] = 0x12
 		}
 	}
-	if m.Seen != 0 {
-		dAtA[i] = 0x18
-		i++
-		i = encodeVarintDatabase(dAtA, i, uint64(m.Seen))
+	if len(m.Key) > 0 {
+		i -= len(m.Key)
+		copy(dAtA[i:], m.Key)
+		i = encodeVarintDatabase(dAtA, i, uint64(len(m.Key)))
+		i--
+		dAtA[i] = 0xa
 	}
-	return i, nil
+	return len(dAtA) - i, nil
 }

 func (m *DatabaseAddress) Marshal() (dAtA []byte, err error) {
 	size := m.Size()
 	dAtA = make([]byte, size)
-	n, err := m.MarshalTo(dAtA)
+	n, err := m.MarshalToSizedBuffer(dAtA[:size])
 	if err != nil {
 		return nil, err
 	}
@@ -161,52 +281,45 @@ func (m *DatabaseAddress) Marshal() (dAtA []byte, err error) {
 }

 func (m *DatabaseAddress) MarshalTo(dAtA []byte) (int, error) {
-	var i int
+	size := m.Size()
+	return m.MarshalToSizedBuffer(dAtA[:size])
+}
+
+func (m *DatabaseAddress) MarshalToSizedBuffer(dAtA []byte) (int, error) {
+	i := len(dAtA)
 	_ = i
 	var l int
 	_ = l
-	if len(m.Address) > 0 {
-		dAtA[i] = 0xa
-		i++
-		i = encodeVarintDatabase(dAtA, i, uint64(len(m.Address)))
-		i += copy(dAtA[i:], m.Address)
-	}
 	if m.Expires != 0 {
-		dAtA[i] = 0x10
-		i++
 		i = encodeVarintDatabase(dAtA, i, uint64(m.Expires))
+		i--
+		dAtA[i] = 0x10
 	}
-	return i, nil
+	if len(m.Address) > 0 {
+		i -= len(m.Address)
+		copy(dAtA[i:], m.Address)
+		i = encodeVarintDatabase(dAtA, i, uint64(len(m.Address)))
+		i--
+		dAtA[i] = 0xa
+	}
+	return len(dAtA) - i, nil
 }

-func encodeFixed64Database(dAtA []byte, offset int, v uint64) int {
-	dAtA[offset] = uint8(v)
-	dAtA[offset+1] = uint8(v >> 8)
-	dAtA[offset+2] = uint8(v >> 16)
-	dAtA[offset+3] = uint8(v >> 24)
-	dAtA[offset+4] = uint8(v >> 32)
-	dAtA[offset+5] = uint8(v >> 40)
-	dAtA[offset+6] = uint8(v >> 48)
-	dAtA[offset+7] = uint8(v >> 56)
-	return offset + 8
-}
-func encodeFixed32Database(dAtA []byte, offset int, v uint32) int {
-	dAtA[offset] = uint8(v)
-	dAtA[offset+1] = uint8(v >> 8)
-	dAtA[offset+2] = uint8(v >> 16)
-	dAtA[offset+3] = uint8(v >> 24)
-	return offset + 4
-}
 func encodeVarintDatabase(dAtA []byte, offset int, v uint64) int {
+	offset -= sovDatabase(v)
+	base := offset
 	for v >= 1<<7 {
 		dAtA[offset] = uint8(v&0x7f | 0x80)
 		v >>= 7
 		offset++
 	}
 	dAtA[offset] = uint8(v)
-	return offset + 1
+	return base
 }
 func (m *DatabaseRecord) Size() (n int) {
+	if m == nil {
+		return 0
+	}
 	var l int
 	_ = l
 	if len(m.Addresses) > 0 {
@@ -221,10 +334,16 @@ func (m *DatabaseRecord) Size() (n int) {
 	if m.Seen != 0 {
 		n += 1 + sovDatabase(uint64(m.Seen))
 	}
+	if m.Missed != 0 {
+		n += 1 + sovDatabase(uint64(m.Missed))
+	}
 	return n
 }

 func (m *ReplicationRecord) Size() (n int) {
+	if m == nil {
+		return 0
+	}
 	var l int
 	_ = l
 	l = len(m.Key)
@@ -244,6 +363,9 @@ func (m *ReplicationRecord) Size() (n int) {
 }

 func (m *DatabaseAddress) Size() (n int) {
+	if m == nil {
+		return 0
+	}
 	var l int
 	_ = l
 	l = len(m.Address)
@@ -257,14 +379,7 @@ func (m *DatabaseAddress) Size() (n int) {
 }

 func sovDatabase(x uint64) (n int) {
-	for {
-		n++
-		x >>= 7
-		if x == 0 {
-			break
-		}
-	}
-	return n
+	return (math_bits.Len64(x|1) + 6) / 7
 }
 func sozDatabase(x uint64) (n int) {
 	return sovDatabase(uint64((x << 1) ^ uint64((int64(x) >> 63))))
@@ -284,7 +399,7 @@ func (m *DatabaseRecord) Unmarshal(dAtA []byte) error {
 			}
 			b := dAtA[iNdEx]
 			iNdEx++
-			wire |= (uint64(b) & 0x7F) << shift
+			wire |= uint64(b&0x7F) << shift
 			if b < 0x80 {
 				break
 			}
@@ -312,7 +427,7 @@ func (m *DatabaseRecord) Unmarshal(dAtA []byte) error {
 				}
 				b := dAtA[iNdEx]
 				iNdEx++
-				msglen |= (int(b) & 0x7F) << shift
+				msglen |= int(b&0x7F) << shift
 				if b < 0x80 {
 					break
 				}
@@ -321,6 +436,9 @@ func (m *DatabaseRecord) Unmarshal(dAtA []byte) error {
 				return ErrInvalidLengthDatabase
 			}
 			postIndex := iNdEx + msglen
+			if postIndex < 0 {
+				return ErrInvalidLengthDatabase
+			}
 			if postIndex > l {
 				return io.ErrUnexpectedEOF
 			}
@@ -343,7 +461,7 @@ func (m *DatabaseRecord) Unmarshal(dAtA []byte) error {
 				}
 				b := dAtA[iNdEx]
 				iNdEx++
-				m.Misses |= (int32(b) & 0x7F) << shift
+				m.Misses |= int32(b&0x7F) << shift
 				if b < 0x80 {
 					break
 				}
@@ -362,7 +480,26 @@ func (m *DatabaseRecord) Unmarshal(dAtA []byte) error {
 				}
 				b := dAtA[iNdEx]
 				iNdEx++
-				m.Seen |= (int64(b) & 0x7F) << shift
+				m.Seen |= int64(b&0x7F) << shift
+				if b < 0x80 {
+					break
+				}
+			}
+		case 4:
+			if wireType != 0 {
+				return fmt.Errorf("proto: wrong wireType = %d for field Missed", wireType)
+			}
+			m.Missed = 0
+			for shift := uint(0); ; shift += 7 {
+				if shift >= 64 {
+					return ErrIntOverflowDatabase
+				}
+				if iNdEx >= l {
+					return io.ErrUnexpectedEOF
+				}
+				b := dAtA[iNdEx]
+				iNdEx++
+				m.Missed |= int64(b&0x7F) << shift
 				if b < 0x80 {
 					break
 				}
@@ -376,6 +513,9 @@ func (m *DatabaseRecord) Unmarshal(dAtA []byte) error {
 			if skippy < 0 {
 				return ErrInvalidLengthDatabase
 			}
+			if (iNdEx + skippy) < 0 {
+				return ErrInvalidLengthDatabase
+			}
 			if (iNdEx + skippy) > l {
 				return io.ErrUnexpectedEOF
 			}
@@ -403,7 +543,7 @@ func (m *ReplicationRecord) Unmarshal(dAtA []byte) error {
 			}
 			b := dAtA[iNdEx]
 			iNdEx++
-			wire |= (uint64(b) & 0x7F) << shift
+			wire |= uint64(b&0x7F) << shift
 			if b < 0x80 {
 				break
 			}
@@ -431,7 +571,7 @@ func (m *ReplicationRecord) Unmarshal(dAtA []byte) error {
 				}
 				b := dAtA[iNdEx]
 				iNdEx++
-				stringLen |= (uint64(b) & 0x7F) << shift
+				stringLen |= uint64(b&0x7F) << shift
 				if b < 0x80 {
 					break
 				}
@@ -441,6 +581,9 @@ func (m *ReplicationRecord) Unmarshal(dAtA []byte) error {
 				return ErrInvalidLengthDatabase
 			}
 			postIndex := iNdEx + intStringLen
+			if postIndex < 0 {
+				return ErrInvalidLengthDatabase
+			}
 			if postIndex > l {
 				return io.ErrUnexpectedEOF
 			}
@@ -460,7 +603,7 @@ func (m *ReplicationRecord) Unmarshal(dAtA []byte) error {
 				}
 				b := dAtA[iNdEx]
 				iNdEx++
-				msglen |= (int(b) & 0x7F) << shift
+				msglen |= int(b&0x7F) << shift
 				if b < 0x80 {
 					break
 				}
@@ -469,6 +612,9 @@ func (m *ReplicationRecord) Unmarshal(dAtA []byte) error {
 				return ErrInvalidLengthDatabase
 			}
 			postIndex := iNdEx + msglen
+			if postIndex < 0 {
+				return ErrInvalidLengthDatabase
+			}
 			if postIndex > l {
 				return io.ErrUnexpectedEOF
 			}
@@ -491,7 +637,7 @@ func (m *ReplicationRecord) Unmarshal(dAtA []byte) error {
 				}
 				b := dAtA[iNdEx]
 				iNdEx++
-				m.Seen |= (int64(b) & 0x7F) << shift
+				m.Seen |= int64(b&0x7F) << shift
 				if b < 0x80 {
 					break
 				}
@@ -505,6 +651,9 @@ func (m *ReplicationRecord) Unmarshal(dAtA []byte) error {
 			if skippy < 0 {
 				return ErrInvalidLengthDatabase
 			}
+			if (iNdEx + skippy) < 0 {
+				return ErrInvalidLengthDatabase
+			}
 			if (iNdEx + skippy) > l {
 				return io.ErrUnexpectedEOF
 			}
@@ -532,7 +681,7 @@ func (m *DatabaseAddress) Unmarshal(dAtA []byte) error {
 			}
 			b := dAtA[iNdEx]
 			iNdEx++
-			wire |= (uint64(b) & 0x7F) << shift
+			wire |= uint64(b&0x7F) << shift
 			if b < 0x80 {
 				break
 			}
@@ -560,7 +709,7 @@ func (m *DatabaseAddress) Unmarshal(dAtA []byte) error {
 				}
 				b := dAtA[iNdEx]
 				iNdEx++
-				stringLen |= (uint64(b) & 0x7F) << shift
+				stringLen |= uint64(b&0x7F) << shift
 				if b < 0x80 {
 					break
 				}
@@ -570,6 +719,9 @@ func (m *DatabaseAddress) Unmarshal(dAtA []byte) error {
 				return ErrInvalidLengthDatabase
 			}
 			postIndex := iNdEx + intStringLen
+			if postIndex < 0 {
+				return ErrInvalidLengthDatabase
+			}
 			if postIndex > l {
 				return io.ErrUnexpectedEOF
 			}
@@ -589,7 +741,7 @@ func (m *DatabaseAddress) Unmarshal(dAtA []byte) error {
 				}
 				b := dAtA[iNdEx]
 				iNdEx++
-				m.Expires |= (int64(b) & 0x7F) << shift
+				m.Expires |= int64(b&0x7F) << shift
 				if b < 0x80 {
 					break
 				}
@@ -603,6 +755,9 @@ func (m *DatabaseAddress) Unmarshal(dAtA []byte) error {
 			if skippy < 0 {
 				return ErrInvalidLengthDatabase
 			}
+			if (iNdEx + skippy) < 0 {
+				return ErrInvalidLengthDatabase
+			}
 			if (iNdEx + skippy) > l {
 				return io.ErrUnexpectedEOF
 			}
@@ -618,6 +773,7 @@ func (m *DatabaseAddress) Unmarshal(dAtA []byte) error {
 func skipDatabase(dAtA []byte) (n int, err error) {
 	l := len(dAtA)
 	iNdEx := 0
+	depth := 0
 	for iNdEx < l {
 		var wire uint64
 		for shift := uint(0); ; shift += 7 {
@@ -649,10 +805,8 @@ func skipDatabase(dAtA []byte) (n int, err error) {
 					break
 				}
 			}
-			return iNdEx, nil
 		case 1:
 			iNdEx += 8
-			return iNdEx, nil
 		case 2:
 			var length int
 			for shift := uint(0); ; shift += 7 {
@@ -669,75 +823,34 @@ func skipDatabase(dAtA []byte) (n int, err error) {
 					break
 				}
 			}
-			iNdEx += length
 			if length < 0 {
 				return 0, ErrInvalidLengthDatabase
 			}
-			return iNdEx, nil
+			iNdEx += length
 		case 3:
-			for {
-				var innerWire uint64
-				var start int = iNdEx
-				for shift := uint(0); ; shift += 7 {
-					if shift >= 64 {
-						return 0, ErrIntOverflowDatabase
-					}
-					if iNdEx >= l {
-						return 0, io.ErrUnexpectedEOF
-					}
-					b := dAtA[iNdEx]
-					iNdEx++
-					innerWire |= (uint64(b) & 0x7F) << shift
-					if b < 0x80 {
-						break
-					}
-				}
-				innerWireType := int(innerWire & 0x7)
-				if innerWireType == 4 {
-					break
-				}
-				next, err := skipDatabase(dAtA[start:])
-				if err != nil {
-					return 0, err
-				}
-				iNdEx = start + next
-			}
-			return iNdEx, nil
+			depth++
 		case 4:
-			return iNdEx, nil
+			if depth == 0 {
+				return 0, ErrUnexpectedEndOfGroupDatabase
+			}
+			depth--
 		case 5:
 			iNdEx += 4
-			return iNdEx, nil
 		default:
 			return 0, fmt.Errorf("proto: illegal wireType %d", wireType)
 		}
+		if iNdEx < 0 {
+			return 0, ErrInvalidLengthDatabase
+		}
+		if depth == 0 {
+			return iNdEx, nil
+		}
 	}
-	panic("unreachable")
+	return 0, io.ErrUnexpectedEOF
 }

 var (
-	ErrInvalidLengthDatabase = fmt.Errorf("proto: negative length found during unmarshaling")
-	ErrIntOverflowDatabase   = fmt.Errorf("proto: integer overflow")
+	ErrInvalidLengthDatabase        = fmt.Errorf("proto: negative length found during unmarshaling")
+	ErrIntOverflowDatabase          = fmt.Errorf("proto: integer overflow")
+	ErrUnexpectedEndOfGroupDatabase = fmt.Errorf("proto: unexpected end of group")
 )
-
-func init() { proto.RegisterFile("database.proto", fileDescriptorDatabase) }
-
-var fileDescriptorDatabase = []byte{
-	// 254 bytes of a gzipped FileDescriptorProto
-	0x1f, 0x8b, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02, 0xff, 0xe2, 0xe2, 0x4b, 0x49, 0x2c, 0x49,
-	0x4c, 0x4a, 0x2c, 0x4e, 0xd5, 0x2b, 0x28, 0xca, 0x2f, 0xc9, 0x17, 0x62, 0xc9, 0x4d, 0xcc, 0xcc,
-	0x93, 0xd2, 0x4d, 0xcf, 0x2c, 0xc9, 0x28, 0x4d, 0xd2, 0x4b, 0xce, 0xcf, 0xd5, 0x4f, 0xcf, 0x4f,
-	0xcf, 0xd7, 0x07, 0x4b, 0x26, 0x95, 0xa6, 0x81, 0x79, 0x60, 0x0e, 0x98, 0x05, 0xd1, 0xa4, 0x54,
-	0xce, 0xc5, 0xe7, 0x02, 0x35, 0x26, 0x28, 0x35, 0x39, 0xbf, 0x28, 0x45, 0xc8, 0x92, 0x8b, 0x33,
-	0x31, 0x25, 0xa5, 0x28, 0xb5, 0xb8, 0x38, 0xb5, 0x58, 0x82, 0x51, 0x81, 0x59, 0x83, 0xdb, 0x48,
-	0x54, 0x0f, 0x64, 0xb4, 0x1e, 0x4c, 0xa1, 0x23, 0x44, 0xda, 0x89, 0xe5, 0xc4, 0x3d, 0x79, 0x86,
-	0x20, 0x84, 0x6a, 0x21, 0x31, 0x2e, 0xb6, 0xdc, 0x4c, 0xb0, 0x3e, 0x26, 0x05, 0x46, 0x0d, 0xd6,
-	0x20, 0x28, 0x4f, 0x48, 0x88, 0x8b, 0xa5, 0x38, 0x35, 0x35, 0x4f, 0x82, 0x59, 0x81, 0x51, 0x83,
-	0x39, 0x08, 0xcc, 0x56, 0x2a, 0xe1, 0x12, 0x0c, 0x4a, 0x2d, 0xc8, 0xc9, 0x4c, 0x4e, 0x2c, 0xc9,
-	0xcc, 0xcf, 0x83, 0xda, 0x2d, 0xc0, 0xc5, 0x9c, 0x9d, 0x5a, 0x29, 0xc1, 0xa8, 0xc0, 0xa8, 0xc1,
-	0x19, 0x04, 0x62, 0xa2, 0xba, 0x86, 0x89, 0x24, 0xd7, 0x60, 0xb3, 0xd5, 0x95, 0x8b, 0x1f, 0x4d,
-	0x9f, 0x90, 0x04, 0x17, 0x3b, 0x54, 0x0f, 0xd4, 0x5e, 0x18, 0x17, 0x24, 0x93, 0x5a, 0x51, 0x90,
-	0x59, 0x04, 0xf5, 0x0f, 0x73, 0x10, 0x8c, 0xeb, 0x24, 0x70, 0xe2, 0xa1, 0x1c, 0xc3, 0x89, 0x47,
-	0x72, 0x8c, 0x17, 0x1e, 0xc9, 0x31, 0x3e, 0x78, 0x24, 0xc7, 0x98, 0xc4, 0x06, 0x0e, 0x4e, 0x63,
-	0x40, 0x00, 0x00, 0x00, 0xff, 0xff, 0x9e, 0x45, 0x60, 0x7e, 0x95, 0x01, 0x00, 0x00,
-}
--- a/cmd/stdiscosrv/database.proto
+++ b/cmd/stdiscosrv/database.proto
@@ -8,16 +8,22 @@ syntax = "proto3";

 package main;

-import "github.com/gogo/protobuf/gogoproto/gogo.proto";
+import "repos/protobuf/gogoproto/gogo.proto";

 option (gogoproto.goproto_getters_all) = false;
+option (gogoproto.goproto_unkeyed_all) = false;
+option (gogoproto.goproto_unrecognized_all) = false;
+option (gogoproto.goproto_sizecache_all) = false;

 message DatabaseRecord {
    repeated DatabaseAddress addresses = 1 [(gogoproto.nullable) = false];
-    int32                    misses    = 2; // Number of lookups without hits
+    int32                    misses    = 2; // Number of lookups* without hits
    int64                    seen      = 3; // Unix nanos, last device announce
+    int64                    missed    = 4; // Unix nanos, last* failed lookup
 }

+// *) Not every lookup results in a write, so may not be completely accurate
+
 message ReplicationRecord {
    string                   key       = 1;
    repeated DatabaseAddress addresses = 2 [(gogoproto.nullable) = false];
--- a/cmd/stdiscosrv/database_test.go
+++ b/cmd/stdiscosrv/database_test.go
@@ -154,7 +154,7 @@ func TestDatabaseGetSet(t *testing.T) {
 	}
 	if len(rec.Addresses) != 1 {
 		t.Log(rec.Addresses)
-		t.Fatal("should have one addres")
+		t.Fatal("should have one address")
 	}
 	if rec.Misses != 0 {
 		t.Log(rec.Misses)
--- a/cmd/stdiscosrv/etc/firewall-ufw/stdiscosrv
+++ b/cmd/stdiscosrv/etc/firewall-ufw/stdiscosrv
@@ -0,0 +1,4 @@
+[stdiscosrv]
+title=Syncthing discovery server
+description=Lets syncthing clients discover each other
+ports=8443/tcp
--- a/cmd/stdiscosrv/etc/linux-systemd/default
+++ b/cmd/stdiscosrv/etc/linux-systemd/default
@@ -0,0 +1,3 @@
+# Default settings for syncthing-relaysrv (strelaysrv).
+## Add Options here:
+DISCOSRV_OPTS=
--- a/cmd/stdiscosrv/etc/linux-systemd/stdiscosrv.service
+++ b/cmd/stdiscosrv/etc/linux-systemd/stdiscosrv.service
@@ -0,0 +1,25 @@
+[Unit]
+Description=Syncthing Discovery Server
+After=network.target
+Documentation=man:stdiscosrv(1)
+
+[Service]
+WorkingDirectory=/var/lib/syncthing-discosrv
+EnvironmentFile=/etc/default/syncthing-discosrv
+ExecStart=/usr/bin/stdiscosrv $DISCOSRV_OPTS
+
+# Hardening
+User=syncthing-discosrv
+Group=syncthing
+ProtectSystem=strict
+ReadWritePaths=/var/lib/syncthing-discosrv
+NoNewPrivileges=true
+PrivateTmp=true
+PrivateDevices=true
+ProtectHome=true
+SystemCallArchitectures=native
+MemoryDenyWriteExecute=true
+
+[Install]
+WantedBy=multi-user.target
+Alias=syncthing-discosrv.service
--- a/cmd/stdiscosrv/main.go
+++ b/cmd/stdiscosrv/main.go
@@ -9,17 +9,15 @@ package main
 import (
 	"crypto/tls"
 	"flag"
-	"fmt"
 	"log"
 	"net"
 	"net/http"
 	"os"
-	"runtime"
-	"strconv"
 	"strings"
 	"time"

 	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"github.com/syncthing/syncthing/lib/build"
 	"github.com/syncthing/syncthing/lib/protocol"
 	"github.com/syncthing/syncthing/lib/tlsutil"
 	"github.com/syndtr/goleveldb/leveldb/opt"
@@ -65,34 +63,11 @@ var levelDBOptions = &opt.Options{
 	WriteBuffer: 32 << 20, // default 4<<20
 }

-var (
-	Version    string
-	BuildStamp string
-	BuildUser  string
-	BuildHost  string
-
-	BuildDate   time.Time
-	LongVersion string
-)
-
-func init() {
-	stamp, _ := strconv.Atoi(BuildStamp)
-	BuildDate = time.Unix(int64(stamp), 0)
-
-	date := BuildDate.UTC().Format("2006-01-02 15:04:05 MST")
-	LongVersion = fmt.Sprintf(`stdiscosrv %s (%s %s-%s) %s@%s %s`, Version, runtime.Version(), runtime.GOOS, runtime.GOARCH, BuildUser, BuildHost, date)
-}
-
 var (
 	debug = false
 )

 func main() {
-	const (
-		cleanIntv = 1 * time.Hour
-		statsIntv = 5 * time.Minute
-	)
-
 	var listen string
 	var dir string
 	var metricsListen string
@@ -114,14 +89,18 @@ func main() {
 	flag.StringVar(&metricsListen, "metrics-listen", "", "Metrics listen address")
 	flag.StringVar(&replicationPeers, "replicate", "", "Replication peers, id@address, comma separated")
 	flag.StringVar(&replicationListen, "replication-listen", ":19200", "Replication listen address")
+	showVersion := flag.Bool("version", false, "Show version")
 	flag.Parse()

-	log.Println(LongVersion)
+	log.Println(build.LongVersion)
+	if *showVersion {
+		return
+	}

 	cert, err := tls.LoadX509KeyPair(certFile, keyFile)
 	if err != nil {
 		log.Println("Failed to load keypair. Generating one, this might take a while...")
-		cert, err = tlsutil.NewCertificate(certFile, keyFile, "stdiscosrv", 0)
+		cert, err = tlsutil.NewCertificate(certFile, keyFile, "stdiscosrv", 20*365)
 		if err != nil {
 			log.Fatalln("Failed to generate X509 key pair:", err)
 		}
@@ -164,7 +143,9 @@ func main() {
 	}

 	// Root of the service tree.
-	main := suture.NewSimple("main")
+	main := suture.New("main", suture.Spec{
+		PassThroughPanics: true,
+	})

 	// Start the database.
 	db, err := newLevelDBStore(dir)
--- a/cmd/stdiscosrv/replication.go
+++ b/cmd/stdiscosrv/replication.go
@@ -18,6 +18,9 @@ import (
 	"github.com/syncthing/syncthing/lib/protocol"
 )

+const replicationReadTimeout = time.Minute
+const replicationHeartbeatInterval = time.Second * 30
+
 type replicator interface {
 	send(key string, addrs []DatabaseAddress, seen int64)
 }
@@ -79,10 +82,22 @@ func (s *replicationSender) Serve() {
 		return
 	}

+	heartBeatTicker := time.NewTicker(replicationHeartbeatInterval)
+	defer heartBeatTicker.Stop()
+
 	// Send records.
 	buf := make([]byte, 1024)
 	for {
 		select {
+		case <-heartBeatTicker.C:
+			if len(s.outbox) > 0 {
+				// No need to send heartbeats if there are events/prevrious
+				// heartbeats to send, they will keep the connection alive.
+				continue
+			}
+			// Empty replication message is the heartbeat:
+			s.outbox <- ReplicationRecord{}
+
 		case rec := <-s.outbox:
 			// Buffer must hold record plus four bytes for size
 			size := rec.Size()
@@ -106,6 +121,7 @@ func (s *replicationSender) Serve() {
 			if _, err := conn.Write(buf[:4+n]); err != nil {
 				replicationSendsTotal.WithLabelValues("error").Inc()
 				log.Println("Replication write:", err)
+				// Yes, we are loosing the replication event here.
 				return
 			}
 			replicationSendsTotal.WithLabelValues("success").Inc()
@@ -149,7 +165,7 @@ func (m replicationMultiplexer) send(key string, ps []DatabaseAddress, seen int6
 	}
 }

-// replicationListener acceptes incoming connections and reads replication
+// replicationListener accepts incoming connections and reads replication
 // items from them. Incoming items are applied to the KV store.
 type replicationListener struct {
 	addr       string
@@ -242,7 +258,7 @@ func (l *replicationListener) handle(conn net.Conn) {
 		default:
 		}

-		conn.SetReadDeadline(time.Now().Add(time.Minute))
+		conn.SetReadDeadline(time.Now().Add(replicationReadTimeout))

 		// First four bytes are the size
 		if _, err := io.ReadFull(conn, buf[:4]); err != nil {
@@ -256,6 +272,12 @@ func (l *replicationListener) handle(conn net.Conn) {
 		if len(buf) < size {
 			buf = make([]byte, size)
 		}
+
+		if size == 0 {
+			// Heartbeat, ignore
+			continue
+		}
+
 		if _, err := io.ReadFull(conn, buf[:size]); err != nil {
 			log.Println("Replication read record:", err)
 			replicationRecvsTotal.WithLabelValues("error").Inc()
--- a/cmd/stdiscosrv/scripts/preinst
+++ b/cmd/stdiscosrv/scripts/preinst
@@ -0,0 +1,4 @@
+#!/bin/bash
+
+addgroup --system syncthing
+adduser --system --home /var/lib/syncthing-discosrv --ingroup syncthing syncthing-discosrv
--- a/cmd/stdiscosrv/stats.go
+++ b/cmd/stdiscosrv/stats.go
@@ -7,6 +7,8 @@
 package main

 import (
+	"os"
+
 	"github.com/prometheus/client_golang/prometheus"
 )

@@ -93,6 +95,7 @@ const (
 	dbOpGet             = "get"
 	dbOpPut             = "put"
 	dbOpMerge           = "merge"
+	dbOpDelete          = "delete"
 	dbResSuccess        = "success"
 	dbResNotFound       = "not_found"
 	dbResError          = "error"
@@ -105,4 +108,16 @@ func init() {
 		replicationSendsTotal, replicationRecvsTotal,
 		databaseKeys, databaseStatisticsSeconds,
 		databaseOperations, databaseOperationSeconds)
+
+	processCollectorOpts := prometheus.ProcessCollectorOpts{
+		Namespace: "syncthing_discovery",
+		PidFn: func() (int, error) {
+			return os.Getpid(), nil
+		},
+	}
+
+	prometheus.MustRegister(
+		prometheus.NewProcessCollector(processCollectorOpts),
+	)
+
 }
--- a/cmd/stfileinfo/main.go
+++ b/cmd/stfileinfo/main.go
@@ -68,8 +68,8 @@ func main() {
 		}

 		blockSize := int(fi.Size())
-		if *standardBlocks || blockSize < protocol.BlockSize {
-			blockSize = protocol.BlockSize
+		if *standardBlocks || blockSize < protocol.MinBlockSize {
+			blockSize = protocol.BlockSize(fi.Size())
 		}
 		bs, err := scanner.Blocks(context.TODO(), fd, blockSize, fi.Size(), nil, true)
 		if err != nil {
--- a/cmd/stfinddevice/main.go
+++ b/cmd/stfinddevice/main.go
@@ -17,6 +17,7 @@ import (

 	"github.com/syncthing/syncthing/lib/config"
 	"github.com/syncthing/syncthing/lib/discover"
+	"github.com/syncthing/syncthing/lib/events"
 	"github.com/syncthing/syncthing/lib/protocol"
 )

@@ -82,7 +83,7 @@ func checkServers(deviceID protocol.DeviceID, servers ...string) {
 }

 func checkServer(deviceID protocol.DeviceID, server string) checkResult {
-	disco, err := discover.NewGlobal(server, tls.Certificate{}, nil)
+	disco, err := discover.NewGlobal(server, tls.Certificate{}, nil, events.NoopLogger)
 	if err != nil {
 		return checkResult{error: err}
 	}
--- a/cmd/stfindignored/main.go
+++ b/cmd/stfindignored/main.go
@@ -0,0 +1,44 @@
+// Copyright (C) 2018 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+// Commmand stfindignored lists ignored files under a given folder root.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+
+	"github.com/syncthing/syncthing/lib/fs"
+	"github.com/syncthing/syncthing/lib/ignore"
+)
+
+func main() {
+	flag.Parse()
+	root := flag.Arg(0)
+	if root == "" {
+		root = "."
+	}
+
+	vfs := fs.NewWalkFilesystem(fs.NewFilesystem(fs.FilesystemTypeBasic, root))
+
+	ign := ignore.New(vfs)
+	if err := ign.Load(".stignore"); err != nil {
+		fmt.Fprintf(os.Stderr, "Fatal: loading ignores: %v\n", err)
+		os.Exit(1)
+	}
+
+	vfs.Walk(".", func(path string, info fs.FileInfo, err error) error {
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Warning: %s: %v\n", path, err)
+			return fs.SkipDir
+		}
+		if ign.Match(path).IsIgnored() {
+			fmt.Println(path)
+		}
+		return nil
+	})
+}
--- a/cmd/stgenfiles/main.go
+++ b/cmd/stgenfiles/main.go
@@ -82,7 +82,7 @@ func generateOneFile(fd io.ReadSeeker, p1 string, s int64) error {
 		return err
 	}

-	_ = os.Chmod(p1, os.FileMode(rand.Intn(0777)|0400))
+	os.Chmod(p1, os.FileMode(rand.Intn(0777)|0400))

 	t := time.Now().Add(-time.Duration(rand.Intn(30*86400)) * time.Second)
 	return os.Chtimes(p1, t, t)
--- a/cmd/stindex/dump.go
+++ b/cmd/stindex/dump.go
@@ -13,11 +13,15 @@ import (
 	"time"

 	"github.com/syncthing/syncthing/lib/db"
+	"github.com/syncthing/syncthing/lib/db/backend"
 	"github.com/syncthing/syncthing/lib/protocol"
 )

-func dump(ldb *db.Instance) {
-	it := ldb.NewIterator(nil, nil)
+func dump(ldb backend.Backend) {
+	it, err := ldb.NewPrefixIterator(nil)
+	if err != nil {
+		log.Fatal(err)
+	}
 	for it.Next() {
 		key := it.Key()
 		switch key[0] {
--- a/cmd/stindex/dumpsize.go
+++ b/cmd/stindex/dumpsize.go
@@ -10,8 +10,10 @@ import (
 	"container/heap"
 	"encoding/binary"
 	"fmt"
+	"log"

 	"github.com/syncthing/syncthing/lib/db"
+	"github.com/syncthing/syncthing/lib/db/backend"
 )

 type SizedElement struct {
@@ -37,11 +39,14 @@ func (h *ElementHeap) Pop() interface{} {
 	return x
 }

-func dumpsize(ldb *db.Instance) {
+func dumpsize(ldb backend.Backend) {
 	h := &ElementHeap{}
 	heap.Init(h)

-	it := ldb.NewIterator(nil, nil)
+	it, err := ldb.NewPrefixIterator(nil)
+	if err != nil {
+		log.Fatal(err)
+	}
 	var ele SizedElement
 	for it.Next() {
 		key := it.Key()
--- a/cmd/stindex/idxck.go
+++ b/cmd/stindex/idxck.go
@@ -0,0 +1,247 @@
+// Copyright (C) 2018 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"bytes"
+	"encoding/binary"
+	"fmt"
+	"log"
+
+	"github.com/syncthing/syncthing/lib/db"
+	"github.com/syncthing/syncthing/lib/db/backend"
+	"github.com/syncthing/syncthing/lib/protocol"
+)
+
+type fileInfoKey struct {
+	folder uint32
+	device uint32
+	name   string
+}
+
+type globalKey struct {
+	folder uint32
+	name   string
+}
+
+type sequenceKey struct {
+	folder   uint32
+	sequence uint64
+}
+
+func idxck(ldb backend.Backend) (success bool) {
+	folders := make(map[uint32]string)
+	devices := make(map[uint32]string)
+	deviceToIDs := make(map[string]uint32)
+	fileInfos := make(map[fileInfoKey]protocol.FileInfo)
+	globals := make(map[globalKey]db.VersionList)
+	sequences := make(map[sequenceKey]string)
+	needs := make(map[globalKey]struct{})
+	var localDeviceKey uint32
+	success = true
+
+	it, err := ldb.NewPrefixIterator(nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+	for it.Next() {
+		key := it.Key()
+		switch key[0] {
+		case db.KeyTypeDevice:
+			folder := binary.BigEndian.Uint32(key[1:])
+			device := binary.BigEndian.Uint32(key[1+4:])
+			name := nulString(key[1+4+4:])
+
+			var f protocol.FileInfo
+			err := f.Unmarshal(it.Value())
+			if err != nil {
+				fmt.Println("Unable to unmarshal FileInfo:", err)
+				success = false
+				continue
+			}
+
+			fileInfos[fileInfoKey{folder, device, name}] = f
+
+		case db.KeyTypeGlobal:
+			folder := binary.BigEndian.Uint32(key[1:])
+			name := nulString(key[1+4:])
+			var flv db.VersionList
+			if err := flv.Unmarshal(it.Value()); err != nil {
+				fmt.Println("Unable to unmarshal VersionList:", err)
+				success = false
+				continue
+			}
+			globals[globalKey{folder, name}] = flv
+
+		case db.KeyTypeFolderIdx:
+			key := binary.BigEndian.Uint32(it.Key()[1:])
+			folders[key] = string(it.Value())
+
+		case db.KeyTypeDeviceIdx:
+			key := binary.BigEndian.Uint32(it.Key()[1:])
+			devices[key] = string(it.Value())
+			deviceToIDs[string(it.Value())] = key
+			if bytes.Equal(it.Value(), protocol.LocalDeviceID[:]) {
+				localDeviceKey = key
+			}
+
+		case db.KeyTypeSequence:
+			folder := binary.BigEndian.Uint32(key[1:])
+			seq := binary.BigEndian.Uint64(key[5:])
+			val := it.Value()
+			sequences[sequenceKey{folder, seq}] = string(val[9:])
+
+		case db.KeyTypeNeed:
+			folder := binary.BigEndian.Uint32(key[1:])
+			name := nulString(key[1+4:])
+			needs[globalKey{folder, name}] = struct{}{}
+		}
+	}
+
+	if localDeviceKey == 0 {
+		fmt.Println("Missing key for local device in device index (bailing out)")
+		success = false
+		return
+	}
+
+	for fk, fi := range fileInfos {
+		if fk.name != fi.Name {
+			fmt.Printf("Mismatching FileInfo name, %q (key) != %q (actual)\n", fk.name, fi.Name)
+			success = false
+		}
+
+		folder := folders[fk.folder]
+		if folder == "" {
+			fmt.Printf("Unknown folder ID %d for FileInfo %q\n", fk.folder, fk.name)
+			success = false
+			continue
+		}
+		if devices[fk.device] == "" {
+			fmt.Printf("Unknown device ID %d for FileInfo %q, folder %q\n", fk.folder, fk.name, folder)
+			success = false
+		}
+
+		if fk.device == localDeviceKey {
+			name, ok := sequences[sequenceKey{fk.folder, uint64(fi.Sequence)}]
+			if !ok {
+				fmt.Printf("Sequence entry missing for FileInfo %q, folder %q, seq %d\n", fi.Name, folder, fi.Sequence)
+				success = false
+				continue
+			}
+			if name != fi.Name {
+				fmt.Printf("Sequence entry refers to wrong name, %q (seq) != %q (FileInfo), folder %q, seq %d\n", name, fi.Name, folder, fi.Sequence)
+				success = false
+			}
+		}
+	}
+
+	for gk, vl := range globals {
+		folder := folders[gk.folder]
+		if folder == "" {
+			fmt.Printf("Unknown folder ID %d for VersionList %q\n", gk.folder, gk.name)
+			success = false
+		}
+		for i, fv := range vl.Versions {
+			dev, ok := deviceToIDs[string(fv.Device)]
+			if !ok {
+				fmt.Printf("VersionList %q, folder %q refers to unknown device %q\n", gk.name, folder, fv.Device)
+				success = false
+			}
+			fi, ok := fileInfos[fileInfoKey{gk.folder, dev, gk.name}]
+			if !ok {
+				fmt.Printf("VersionList %q, folder %q, entry %d refers to unknown FileInfo\n", gk.name, folder, i)
+				success = false
+			}
+			if !fi.Version.Equal(fv.Version) {
+				fmt.Printf("VersionList %q, folder %q, entry %d, FileInfo version mismatch, %v (VersionList) != %v (FileInfo)\n", gk.name, folder, i, fv.Version, fi.Version)
+				success = false
+			}
+			if fi.IsInvalid() != fv.Invalid {
+				fmt.Printf("VersionList %q, folder %q, entry %d, FileInfo invalid mismatch, %v (VersionList) != %v (FileInfo)\n", gk.name, folder, i, fv.Invalid, fi.IsInvalid())
+				success = false
+			}
+		}
+
+		// If we need this file we should have a need entry for it. False
+		// positives from needsLocally for deleted files, where we might
+		// legitimately lack an entry if we never had it, and ignored files.
+		if needsLocally(vl) {
+			_, ok := needs[gk]
+			if !ok {
+				dev := deviceToIDs[string(vl.Versions[0].Device)]
+				fi := fileInfos[fileInfoKey{gk.folder, dev, gk.name}]
+				if !fi.IsDeleted() && !fi.IsIgnored() {
+					fmt.Printf("Missing need entry for needed file %q, folder %q\n", gk.name, folder)
+				}
+			}
+		}
+	}
+
+	seenSeq := make(map[fileInfoKey]uint64)
+	for sk, name := range sequences {
+		folder := folders[sk.folder]
+		if folder == "" {
+			fmt.Printf("Unknown folder ID %d for sequence entry %d, %q\n", sk.folder, sk.sequence, name)
+			success = false
+			continue
+		}
+
+		if prev, ok := seenSeq[fileInfoKey{folder: sk.folder, name: name}]; ok {
+			fmt.Printf("Duplicate sequence entry for %q, folder %q, seq %d (prev %d)\n", name, folder, sk.sequence, prev)
+			success = false
+		}
+		seenSeq[fileInfoKey{folder: sk.folder, name: name}] = sk.sequence
+
+		fi, ok := fileInfos[fileInfoKey{sk.folder, localDeviceKey, name}]
+		if !ok {
+			fmt.Printf("Missing FileInfo for sequence entry %d, folder %q, %q\n", sk.sequence, folder, name)
+			success = false
+			continue
+		}
+		if fi.Sequence != int64(sk.sequence) {
+			fmt.Printf("Sequence mismatch for %q, folder %q, %d (key) != %d (FileInfo)\n", name, folder, sk.sequence, fi.Sequence)
+			success = false
+		}
+	}
+
+	for nk := range needs {
+		folder := folders[nk.folder]
+		if folder == "" {
+			fmt.Printf("Unknown folder ID %d for need entry %q\n", nk.folder, nk.name)
+			success = false
+			continue
+		}
+
+		vl, ok := globals[nk]
+		if !ok {
+			fmt.Printf("Missing global for need entry %q, folder %q\n", nk.name, folder)
+			success = false
+			continue
+		}
+
+		if !needsLocally(vl) {
+			fmt.Printf("Need entry for file we don't need, %q, folder %q\n", nk.name, folder)
+			success = false
+		}
+	}
+
+	return
+}
+
+func needsLocally(vl db.VersionList) bool {
+	var lv *protocol.Vector
+	for _, fv := range vl.Versions {
+		if bytes.Equal(fv.Device, protocol.LocalDeviceID[:]) {
+			lv = &fv.Version
+			break
+		}
+	}
+	if lv == nil {
+		return true // proviosinally, it looks like we need the file
+	}
+	return !lv.GreaterEqual(vl.Versions[0].Version)
+}
--- a/cmd/stindex/main.go
+++ b/cmd/stindex/main.go
@@ -13,7 +13,7 @@ import (
 	"os"
 	"path/filepath"

-	"github.com/syncthing/syncthing/lib/db"
+	"github.com/syncthing/syncthing/lib/db/backend"
 )

 func main() {
@@ -21,7 +21,7 @@ func main() {
 	log.SetFlags(0)
 	log.SetOutput(os.Stdout)

-	flag.StringVar(&mode, "mode", "dump", "Mode of operation: dump, dumpsize")
+	flag.StringVar(&mode, "mode", "dump", "Mode of operation: dump, dumpsize, idxck")

 	flag.Parse()

@@ -30,9 +30,7 @@ func main() {
 		path = filepath.Join(defaultConfigDir(), "index-v0.14.0.db")
 	}

-	fmt.Println("Path:", path)
-
-	ldb, err := db.Open(path)
+	ldb, err := backend.OpenLevelDBRO(path)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -41,6 +39,10 @@ func main() {
 		dump(ldb)
 	} else if mode == "dumpsize" {
 		dumpsize(ldb)
+	} else if mode == "idxck" {
+		if !idxck(ldb) {
+			os.Exit(1)
+		}
 	} else {
 		fmt.Println("Unknown mode")
 	}
--- a/cmd/strelaypoolsrv/auto/.gitignore
+++ b/cmd/strelaypoolsrv/auto/.gitignore
@@ -1 +1 @@
-gui.go
+gui.files.go
--- a/cmd/strelaypoolsrv/auto/doc.go
+++ b/cmd/strelaypoolsrv/auto/doc.go
@@ -0,0 +1,10 @@
+// Copyright (C) 2018 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+//go:generate go run ../../../script/genassets.go -o gui.files.go ../gui
+
+// Package auto contains auto generated files for web assets.
+package auto
--- a/cmd/strelaypoolsrv/gui/index.html
+++ b/cmd/strelaypoolsrv/gui/index.html
@@ -10,7 +10,7 @@

    <title>Relay stats</title>
    <link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css" rel="stylesheet"/>
-    <link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/font-awesome/4.6.1/css/font-awesome.min.css"/>
+    <link rel="stylesheet" href="//use.fontawesome.com/releases/v5.0.13/css/all.css"/>

    <style>
      #map {
@@ -56,83 +56,83 @@
            <tr>
              <th rowspan="2">Address</td>
              <th rowspan="2">
-                <a ng-click="sortType = 'status.numActiveSessions'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.numActiveSessions'; sortReverse = !sortReverse">
                  Sessions
-                  <span ng-show="sortType == 'status.numActiveSessions' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.numActiveSessions' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.numActiveSessions' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.numActiveSessions' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th rowspan="2">
-                <a ng-click="sortType = 'status.numConnections'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.numConnections'; sortReverse = !sortReverse">
                  Connections
-                  <span ng-show="sortType == 'status.numConnections' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.numConnections' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.numConnections' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.numConnections' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th rowspan="2">
-                <a ng-click="sortType = 'status.bytesProxied'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.bytesProxied'; sortReverse = !sortReverse">
                  Data relayed
-                  <span ng-show="sortType == 'status.bytesProxied' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.bytesProxied' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.bytesProxied' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.bytesProxied' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th colspan="6" class="text-center">Transfer rate in the last period</th>
              <th rowspan="2">
-                <a ng-click="sortType = 'status.uptimeSeconds'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.uptimeSeconds'; sortReverse = !sortReverse">
                  Uptime hours
-                  <span ng-show="sortType == 'status.uptimeSeconds' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.uptimeSeconds' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.uptimeSeconds' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'status.uptimeSeconds' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th rowspan="2">
-                <a ng-click="sortType = 'status.options[\'provided-by\'] || \'\''; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.options[\'provided-by\'] || \'\''; sortReverse = !sortReverse">
                  Provided by
-                  <span ng-show="sortType == 'status.options[\'provided-by\'] || \'\'' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.options[\'provided-by\'] || \'\'' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.options[\'provided-by\'] || \'\'' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.options[\'provided-by\'] || \'\'' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
            </tr>
            <tr>
              <th>
-                <a ng-click="sortType = 'status.kbps10s1m5m15m30m60m[0]'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.kbps10s1m5m15m30m60m[0]'; sortReverse = !sortReverse">
                  10s
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[0]' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[0]' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[0]' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[0]' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th>
-                <a ng-click="sortType = 'status.kbps10s1m5m15m30m60m[1]'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.kbps10s1m5m15m30m60m[1]'; sortReverse = !sortReverse">
                  1m
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[1]' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[1]' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[1]' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[1]' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th>
-                <a ng-click="sortType = 'status.kbps10s1m5m15m30m60m[2]'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.kbps10s1m5m15m30m60m[2]'; sortReverse = !sortReverse">
                  5m
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[2]' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[2]' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[2]' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[2]' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th>
-                <a ng-click="sortType = 'status.kbps10s1m5m15m30m60m[3]'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.kbps10s1m5m15m30m60m[3]'; sortReverse = !sortReverse">
                  15m
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[3]' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[3]' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[3]' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[3]' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th>
-                <a ng-click="sortType = 'status.kbps10s1m5m15m30m60m[4]'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.kbps10s1m5m15m30m60m[4]'; sortReverse = !sortReverse">
                  30m
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[4]' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[4]' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[4]' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[4]' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
              <th>
-                <a ng-click="sortType = 'status.kbps10s1m5m15m30m60m[5]'; sortReverse = !sortReverse">
+                <a ng-click="sortType = 'stats.kbps10s1m5m15m30m60m[5]'; sortReverse = !sortReverse">
                  60m
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[5]' && !sortReverse" class="fa fa-caret-down"></span>
-                  <span ng-show="sortType == 'status.kbps10s1m5m15m30m60m[5]' && sortReverse" class="fa fa-caret-up"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[5]' && !sortReverse" class="fas fa-caret-down"></span>
+                  <span ng-show="sortType == 'stats.kbps10s1m5m15m30m60m[5]' && sortReverse" class="fas fa-caret-up"></span>
                </a>
              </th>
            </tr>
@@ -140,21 +140,21 @@
          <tbody>
            <tr ng-repeat="relay in relays | orderBy:sortType:sortReverse:sortCompare" ng-mouseover="relay.showMarker()" ng-mouseleave="relay.hideMarker()">
              <td>{{ relay.address }}</td>
-              <td ng-if="relay.status === undefined" colspan="11" class="text-center">Looking up...</td>
-              <td ng-if-start="relay.status !== undefined">{{ relay.status.numActiveSessions }}</td>
-              <td>{{ relay.status.numConnections }}</td>
-              <td>{{ relay.status.bytesProxied | bytes }}</td>
-              <td>{{ relay.status.kbps10s1m5m15m30m60m[0] * 128 | bytes }}/s</td>
-              <td>{{ relay.status.kbps10s1m5m15m30m60m[1] * 128 | bytes }}/s</td>
-              <td>{{ relay.status.kbps10s1m5m15m30m60m[2] * 128 | bytes }}/s</td>
-              <td>{{ relay.status.kbps10s1m5m15m30m60m[3] * 128 | bytes }}/s</td>
-              <td>{{ relay.status.kbps10s1m5m15m30m60m[4] * 128 | bytes }}/s</td>
-              <td>{{ relay.status.kbps10s1m5m15m30m60m[5] * 128 | bytes }}/s</td>
-              <td ng-if="relay.status.uptimeSeconds != undefined">{{ relay.status.uptimeSeconds/60/60 | number:0 }}</td>
-              <td ng-if="relay.status.uptimeSeconds == undefined"></td>
-              <td title="{{ relay.status.options['provided-by'] || '' }}" ng-if-end>
-                {{ relay.status.options['provided-by'] || '' | limitTo:50 }}
-                <span ng-if="(relay.status.options['provided-by'] || '').length > 50">&hellip;
+              <td ng-if="!relay.stats" colspan="11"></td>
+              <td ng-if-start="relay.stats">{{ relay.stats.numActiveSessions }}</td>
+              <td>{{ relay.stats.numConnections }}</td>
+              <td>{{ relay.stats.bytesProxied | bytes }}</td>
+              <td>{{ relay.stats.kbps10s1m5m15m30m60m[0] * 128 | bytes }}/s</td>
+              <td>{{ relay.stats.kbps10s1m5m15m30m60m[1] * 128 | bytes }}/s</td>
+              <td>{{ relay.stats.kbps10s1m5m15m30m60m[2] * 128 | bytes }}/s</td>
+              <td>{{ relay.stats.kbps10s1m5m15m30m60m[3] * 128 | bytes }}/s</td>
+              <td>{{ relay.stats.kbps10s1m5m15m30m60m[4] * 128 | bytes }}/s</td>
+              <td>{{ relay.stats.kbps10s1m5m15m30m60m[5] * 128 | bytes }}/s</td>
+              <td ng-if="relay.stats.uptimeSeconds != undefined">{{ relay.stats.uptimeSeconds/60/60 | number:0 }}</td>
+              <td ng-if="relay.stats.uptimeSeconds == undefined"></td>
+              <td title="{{ relay.stats.options['provided-by'] || '' }}" ng-if-end>
+                {{ relay.stats.options['provided-by'] || '' | limitTo:50 }}
+                <span ng-if="(relay.stats.options['provided-by'] || '').length > 50">&hellip;
              </td>
            </tr>
          </tbody>
@@ -187,15 +187,15 @@
    <script type="text/javascript" src="//code.jquery.com/jquery-2.1.4.min.js"></script>
    <script type="text/javascript" src="//cdnjs.cloudflare.com/ajax/libs/angular.js/1.5.8/angular.min.js"></script>
    <script type="text/javascript" src="//maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>
-    <script type="text/javascript" src="//maps.googleapis.com/maps/api/js"></script>
+    <script type="text/javascript" src="//maps.googleapis.com/maps/api/js?key=AIzaSyDk5WJ8s7ueLKb99X5DbQ-vkWtPDAKqYs0"></script>
  </body>

  <script>
  angular.module('syncthing', [
  ])
-  .config(function($httpProvider) {
+  .config(['$httpProvider', function($httpProvider) {
    $httpProvider.defaults.timeout = 5000;
-  })
+  }])
  .filter('bytes', function() {
    return function(bytes, precision) {
      if (isNaN(parseFloat(bytes)) || !isFinite(bytes)) return '-';
@@ -235,16 +235,16 @@
    $scope.mapBounds = new google.maps.LatLngBounds();
    $scope.tooltipTemplate = $('#infoTemplate').html();
    $scope.usedLocations = {};
-    $scope.sortType = 'status.numActiveSessions';
+    $scope.sortType = 'stats.numActiveSessions';
    $scope.sortReverse = true;
    $scope.sortCompare = function(a, b) {
      if (a.value == b.value) {
        return 0;
      }
-      if (a.type == "undefined") {
+      if (a.type == "undefined" || a.type == "null") {
        return -1;
      }
-      if (b.type == "undefined") {
+      if (b.type == "undefined" || b.type == "null") {
        return 1;
      }
      return a.value > b.value ? 1 : -1;
@@ -252,25 +252,31 @@

    $http.get("/endpoint").then(function(response) {
      $scope.relays = response.data.relays;
-      var promises = [];
-      angular.forEach($scope.relays, function(relay) {

+      angular.forEach($scope.relays, function(relay) {
        relay.uri = constructURI(relay.url);
        relay.address = relay.url.split('/')[2];

        addMarkerToMap(relay);

-        promises.push(getRelayStatus(relay));
+        if (relay.stats) {
+          angular.forEach($scope.totals, function(value, key) {
+            if (typeof $scope.totals[key] == 'number') {
+              $scope.totals[key] += relay.stats[key];
+            } else if (typeof $scope.totals[key] == 'object' && $scope.totals[key] instanceof Array) {
+              angular.forEach($scope.totals[key], function(value, index) {
+                $scope.totals[key][index] += relay.stats[key][index];
+              });
+            }
+          });
+        }
      });

-      // Can only add circles once we know the totals for transfers, which means
-      // we need to resolve all statuses.
-      $q.all(promises).then(function() {
-        angular.forEach($scope.relays, function(relay) {
-          if (relay.status) {
-            addCircleToMap(relay);
-          }
-        });
+      // After the totals were calculated, add circles.
+      angular.forEach($scope.relays, function(relay) {
+        if (relay.stats) {
+          addCircleToMap(relay);
+        }
      });

      $scope.map.fitBounds($scope.mapBounds);
@@ -330,41 +336,10 @@
        fillOpacity: 0.35,
        map: $scope.map,
        center: relay.marker.position,
-        radius: ((relay.status.bytesProxied * 100) / $scope.totals.bytesProxied) * 10000
+        radius: ((relay.stats.bytesProxied * 100) / $scope.totals.bytesProxied) * 10000
      });
    }

-    function getRelayStatus(relay) {
-      // Normal timeout doesn't deal with relays which accept the TCP connection
-      // but don't respond (some firewalls do that), so deal with it this way.
-      var timeoutRequest = $q.defer();
-      var resolveStatus = $q.defer();
-
-
-      $http.get("http://" + relay.uri.hostname + ':' + ((relay.uri.args.statusAddr && relay.uri.args.statusAddr.split(':')[1]) || "22070") + "/status", { timeout: timeoutRequest.promise }).then(function (response) {
-        relay.status = response.data;
-        resolveStatus.resolve();
-        angular.forEach($scope.totals, function(value, key) {
-          if (typeof $scope.totals[key] == 'number') {
-            $scope.totals[key] += response.data[key];
-          } else if (typeof $scope.totals[key] == 'object' && $scope.totals[key] instanceof Array) {
-            angular.forEach($scope.totals[key], function(value, index) {
-              $scope.totals[key][index] += response.data[key][index];
-            });
-          }
-        });
-      }, function() {
-        relay.status = null;
-        resolveStatus.resolve();
-      });
-
-      $timeout(function() {
-        timeoutRequest.resolve();
-      }, 5000);
-
-      return resolveStatus.promise;
-    }
-
    function constructURI(url) {
      var uri = document.createElement('a');

@@ -385,25 +360,25 @@

  <script type="text/template" id="infoTemplate">
    <div>
-      <p><b>{{ relay.uri.hostname }}</b> <span ng-if="relay.status.options['provided-by']">provided by <u>{{ relay.status.options['provided-by'] }}</u></span></p>
-      <div ng-if="relay.status">
-        <span ng-if="relay.status.startTime">Start time: {{ relay.status.startTime | date:"medium" }}</br></span>
-        <span ng-if="relay.status.bytesProxied != undefined">Proxied: {{ relay.status.bytesProxied | bytes }}</br></span>
-        <span ng-if="relay.status.numActiveSessions != undefined">Sessions: {{ relay.status.numActiveSessions }}</br></span>
-        <span ng-if="relay.status.numConnections != undefined">Clients: {{ relay.status.numConnections }}</br></span>
-        <span ng-if="relay.status.options.pools">Pools: {{ relay.status.options.pools.join(', ') }}</br></span>
-        <span ng-if="relay.status.options['global-rate'] != undefined">
-          <span ng-if="relay.status.options['global-rate'] > 0">Global rate limit: {{ relay.status.options['global-rate'] | bytes }}/s</span>
-          <span ng-if="relay.status.options['global-rate'] == 0">Global rate limit: unlimited</span>
+      <p><b>{{ relay.uri.hostname }}</b> <span ng-if="relay.stats.options['provided-by']">provided by <u>{{ relay.stats.options['provided-by'] }}</u></span></p>
+      <div ng-if="relay.stats">
+        <span ng-if="relay.stats.startTime">Start time: {{ relay.stats.startTime | date:"medium" }}</br></span>
+        <span ng-if="relay.stats.bytesProxied != undefined">Proxied: {{ relay.stats.bytesProxied | bytes }}</br></span>
+        <span ng-if="relay.stats.numActiveSessions != undefined">Sessions: {{ relay.stats.numActiveSessions }}</br></span>
+        <span ng-if="relay.stats.numConnections != undefined">Clients: {{ relay.stats.numConnections }}</br></span>
+        <span ng-if="relay.stats.options.pools">Pools: {{ relay.stats.options.pools.join(', ') }}</br></span>
+        <span ng-if="relay.stats.options['global-rate'] != undefined">
+          <span ng-if="relay.stats.options['global-rate'] > 0">Global rate limit: {{ relay.stats.options['global-rate'] | bytes }}/s</span>
+          <span ng-if="relay.stats.options['global-rate'] == 0">Global rate limit: unlimited</span>
          <br/>
        </span>
-        <span ng-if="relay.status.options['per-session-rate'] != undefined">
-          <span ng-if="relay.status.options['per-session-rate'] > 0">Session rate limit: {{ relay.status.options['per-session-rate'] | bytes }}/s</span>
-          <span ng-if="relay.status.options['per-session-rate'] == 0">Session rate limit: unlimited</span>
+        <span ng-if="relay.stats.options['per-session-rate'] != undefined">
+          <span ng-if="relay.stats.options['per-session-rate'] > 0">Session rate limit: {{ relay.stats.options['per-session-rate'] | bytes }}/s</span>
+          <span ng-if="relay.stats.options['per-session-rate'] == 0">Session rate limit: unlimited</span>
          <br/>
        </span>
      </div>
-      <div ng-if="!relay.status">
+      <div ng-if="!relay.stats">
        Data unavailable.
      <div>
    </div>
--- a/cmd/strelaypoolsrv/main.go
+++ b/cmd/strelaypoolsrv/main.go
@@ -7,24 +7,29 @@ package main
 import (
 	"bytes"
 	"compress/gzip"
+	"context"
 	"crypto/tls"
 	"encoding/json"
 	"flag"
 	"fmt"
 	"io/ioutil"
 	"log"
-	"math/rand"
 	"mime"
 	"net"
 	"net/http"
 	"net/url"
+	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 	"time"

 	"github.com/golang/groupcache/lru"
 	"github.com/oschwald/geoip2-golang"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/syncthing/syncthing/cmd/strelaypoolsrv/auto"
+	"github.com/syncthing/syncthing/lib/rand"
 	"github.com/syncthing/syncthing/lib/relay/client"
 	"github.com/syncthing/syncthing/lib/sync"
 	"github.com/syncthing/syncthing/lib/tlsutil"
@@ -34,12 +39,42 @@ import (
 type location struct {
 	Latitude  float64 `json:"latitude"`
 	Longitude float64 `json:"longitude"`
+	City      string  `json:"city"`
+	Country   string  `json:"country"`
+	Continent string  `json:"continent"`
 }

 type relay struct {
-	URL      string   `json:"url"`
-	Location location `json:"location"`
-	uri      *url.URL
+	URL            string   `json:"url"`
+	Location       location `json:"location"`
+	uri            *url.URL
+	Stats          *stats    `json:"stats"`
+	StatsRetrieved time.Time `json:"statsRetrieved"`
+}
+
+type stats struct {
+	StartTime          time.Time `json:"startTime"`
+	UptimeSeconds      int       `json:"uptimeSeconds"`
+	PendingSessionKeys int       `json:"numPendingSessionKeys"`
+	ActiveSessions     int       `json:"numActiveSessions"`
+	Connections        int       `json:"numConnections"`
+	Proxies            int       `json:"numProxies"`
+	BytesProxied       int       `json:"bytesProxied"`
+	GoVersion          string    `json:"goVersion"`
+	GoOS               string    `json:"goOS"`
+	GoArch             string    `json:"goArch"`
+	GoMaxProcs         int       `json:"goMaxProcs"`
+	GoRoutines         int       `json:"goNumRoutine"`
+	Rates              []int64   `json:"kbps10s1m5m15m30m60m"`
+	Options            struct {
+		NetworkTimeout int      `json:"network-timeout"`
+		PintInterval   int      `json:"ping-interval"`
+		MessageTimeout int      `json:"message-timeout"`
+		SessionRate    int      `json:"per-session-rate"`
+		GlobalRate     int      `json:"global-rate"`
+		Pools          []string `json:"pools"`
+		ProvidedBy     string   `json:"provided-by"`
+	} `json:"options"`
 }

 func (r relay) String() string {
@@ -47,9 +82,9 @@ func (r relay) String() string {
 }

 type request struct {
-	relay  relay
-	uri    *url.URL
-	result chan result
+	relay      *relay
+	result     chan result
+	queueTimer *prometheus.Timer
 }

 type result struct {
@@ -58,23 +93,25 @@ type result struct {
 }

 var (
-	testCert       tls.Certificate
-	listen         = ":80"
-	dir            string
-	evictionTime   = time.Hour
-	debug          bool
-	getLRUSize     = 10 << 10
-	getLimitBurst  = 10
-	getLimitAvg    = 1
-	postLRUSize    = 1 << 10
-	postLimitBurst = 2
-	postLimitAvg   = 1
-	getLimit       time.Duration
-	postLimit      time.Duration
-	permRelaysFile string
-	ipHeader       string
-	geoipPath      string
-	proto          string
+	testCert        tls.Certificate
+	knownRelaysFile = filepath.Join(os.TempDir(), "strelaypoolsrv_known_relays")
+	listen          = ":80"
+	dir             string
+	evictionTime    = time.Hour
+	debug           bool
+	getLRUSize      = 10 << 10
+	getLimitBurst   = 10
+	getLimitAvg     = 2
+	postLRUSize     = 1 << 10
+	postLimitBurst  = 2
+	postLimitAvg    = 2
+	getLimit        time.Duration
+	postLimit       time.Duration
+	permRelaysFile  string
+	ipHeader        string
+	geoipPath       string
+	proto           string
+	statsRefresh    = time.Minute / 2

 	getMut      = sync.NewRWMutex()
 	getLRUCache *lru.Cache
@@ -85,26 +122,31 @@ var (
 	requests = make(chan request, 10)

 	mut             = sync.NewRWMutex()
-	knownRelays     = make([]relay, 0)
-	permanentRelays = make([]relay, 0)
+	knownRelays     = make([]*relay, 0)
+	permanentRelays = make([]*relay, 0)
 	evictionTimers  = make(map[string]*time.Timer)
 )

+const (
+	httpStatusEnhanceYourCalm = 429
+)
+
 func main() {
 	flag.StringVar(&listen, "listen", listen, "Listen address")
 	flag.StringVar(&dir, "keys", dir, "Directory where http-cert.pem and http-key.pem is stored for TLS listening")
 	flag.BoolVar(&debug, "debug", debug, "Enable debug output")
 	flag.DurationVar(&evictionTime, "eviction", evictionTime, "After how long the relay is evicted")
 	flag.IntVar(&getLRUSize, "get-limit-cache", getLRUSize, "Get request limiter cache size")
-	flag.IntVar(&getLimitAvg, "get-limit-avg", 2, "Allowed average get request rate, per 10 s")
+	flag.IntVar(&getLimitAvg, "get-limit-avg", getLimitAvg, "Allowed average get request rate, per 10 s")
 	flag.IntVar(&getLimitBurst, "get-limit-burst", getLimitBurst, "Allowed burst get requests")
 	flag.IntVar(&postLRUSize, "post-limit-cache", postLRUSize, "Post request limiter cache size")
-	flag.IntVar(&postLimitAvg, "post-limit-avg", 2, "Allowed average post request rate, per minute")
+	flag.IntVar(&postLimitAvg, "post-limit-avg", postLimitAvg, "Allowed average post request rate, per minute")
 	flag.IntVar(&postLimitBurst, "post-limit-burst", postLimitBurst, "Allowed burst post requests")
 	flag.StringVar(&permRelaysFile, "perm-relays", "", "Path to list of permanent relays")
 	flag.StringVar(&ipHeader, "ip-header", "", "Name of header which holds clients ip:port. Only meaningful when running behind a reverse proxy.")
 	flag.StringVar(&geoipPath, "geoip", "GeoLite2-City.mmdb", "Path to GeoLite2-City database")
 	flag.StringVar(&proto, "protocol", "tcp", "Protocol used for listening. 'tcp' for IPv4 and IPv6, 'tcp4' for IPv4, 'tcp6' for IPv6")
+	flag.DurationVar(&statsRefresh, "stats-refresh", statsRefresh, "Interval at which to refresh relay stats")

 	flag.Parse()

@@ -118,13 +160,31 @@ func main() {
 	var err error

 	if permRelaysFile != "" {
-		loadPermanentRelays(permRelaysFile)
+		permanentRelays = loadRelays(permRelaysFile)
 	}

 	testCert = createTestCertificate()

 	go requestProcessor()

+	// Load relays from cache in the background.
+	// Load them in a serial fashion to make sure any genuine requests
+	// are not dropped.
+	go func() {
+		for _, relay := range loadRelays(knownRelaysFile) {
+			resultChan := make(chan result)
+			requests <- request{relay, resultChan, nil}
+			result := <-resultChan
+			if result.err != nil {
+				relayTestsTotal.WithLabelValues("failed").Inc()
+			} else {
+				relayTestsTotal.WithLabelValues("success").Inc()
+			}
+		}
+		// Run the the stats refresher once the relays are loaded.
+		statsRefresher(statsRefresh)
+	}()
+
 	if dir != "" {
 		if debug {
 			log.Println("Starting TLS listener on", listen)
@@ -169,6 +229,7 @@ func main() {
 	handler := http.NewServeMux()
 	handler.HandleFunc("/", handleAssets)
 	handler.HandleFunc("/endpoint", handleRequest)
+	handler.HandleFunc("/metrics", handleMetrics)

 	srv := http.Server{
 		Handler:     handler,
@@ -181,7 +242,18 @@ func main() {
 	}
 }

+func handleMetrics(w http.ResponseWriter, r *http.Request) {
+	timer := prometheus.NewTimer(metricsRequestsSeconds)
+	// Acquire the mutex just to make sure we're not caught mid-way stats collection
+	mut.RLock()
+	promhttp.Handler().ServeHTTP(w, r)
+	mut.RUnlock()
+	timer.ObserveDuration()
+}
+
 func handleAssets(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Cache-Control", "no-cache, must-revalidate")
+
 	assets := auto.Assets()
 	path := r.URL.Path[1:]
 	if path == "" {
@@ -194,11 +266,28 @@ func handleAssets(w http.ResponseWriter, r *http.Request) {
 		return
 	}

+	etag := fmt.Sprintf("%d", auto.Generated)
+	modified := time.Unix(auto.Generated, 0).UTC()
+
+	w.Header().Set("Last-Modified", modified.Format(http.TimeFormat))
+	w.Header().Set("Etag", etag)
+
 	mtype := mimeTypeForFile(path)
 	if len(mtype) != 0 {
 		w.Header().Set("Content-Type", mtype)
 	}

+	if t, err := time.Parse(http.TimeFormat, r.Header.Get("If-Modified-Since")); err == nil && modified.Add(time.Second).After(t) {
+		w.WriteHeader(http.StatusNotModified)
+		return
+	}
+
+	if match := r.Header.Get("If-None-Match"); match != "" {
+		if strings.Contains(match, etag) {
+			w.WriteHeader(http.StatusNotModified)
+			return
+		}
+	}
 	if strings.Contains(r.Header.Get("Accept-Encoding"), "gzip") {
 		w.Header().Set("Content-Encoding", "gzip")
 	} else {
@@ -241,6 +330,15 @@ func mimeTypeForFile(file string) string {
 }

 func handleRequest(w http.ResponseWriter, r *http.Request) {
+	timer := prometheus.NewTimer(apiRequestsSeconds.WithLabelValues(r.Method))
+
+	lw := NewLoggingResponseWriter(w)
+
+	defer func() {
+		timer.ObserveDuration()
+		apiRequestsTotal.WithLabelValues(r.Method, strconv.Itoa(lw.statusCode)).Inc()
+	}()
+
 	if ipHeader != "" {
 		r.RemoteAddr = r.Header.Get(ipHeader)
 	}
@@ -248,13 +346,13 @@ func handleRequest(w http.ResponseWriter, r *http.Request) {
 	switch r.Method {
 	case "GET":
 		if limit(r.RemoteAddr, getLRUCache, getMut, getLimit, getLimitBurst) {
-			w.WriteHeader(429)
+			w.WriteHeader(httpStatusEnhanceYourCalm)
 			return
 		}
 		handleGetRequest(w, r)
 	case "POST":
 		if limit(r.RemoteAddr, postLRUCache, postMut, postLimit, postLimitBurst) {
-			w.WriteHeader(429)
+			w.WriteHeader(httpStatusEnhanceYourCalm)
 			return
 		}
 		handlePostRequest(w, r)
@@ -273,12 +371,9 @@ func handleGetRequest(w http.ResponseWriter, r *http.Request) {
 	mut.RUnlock()

 	// Shuffle
-	for i := range relays {
-		j := rand.Intn(i + 1)
-		relays[i], relays[j] = relays[j], relays[i]
-	}
+	rand.Shuffle(relays)

-	json.NewEncoder(w).Encode(map[string][]relay{
+	json.NewEncoder(w).Encode(map[string][]*relay{
 		"relays": relays,
 	})
 }
@@ -315,13 +410,9 @@ func handlePostRequest(w http.ResponseWriter, r *http.Request) {
 	}

 	// Get the IP address of the client
-	rhost, _, err := net.SplitHostPort(r.RemoteAddr)
-	if err != nil {
-		if debug {
-			log.Println("Failed to split remote address", r.RemoteAddr)
-		}
-		http.Error(w, err.Error(), 500)
-		return
+	rhost := r.RemoteAddr
+	if host, _, err := net.SplitHostPort(rhost); err == nil {
+		rhost = host
 	}

 	ip := net.ParseIP(host)
@@ -333,18 +424,18 @@ func handlePostRequest(w http.ResponseWriter, r *http.Request) {
 		if debug {
 			log.Println("IP address advertised does not match client IP address", r.RemoteAddr, uri)
 		}
-		http.Error(w, "IP address does not match client IP", http.StatusUnauthorized)
+		http.Error(w, fmt.Sprintf("IP advertised %s does not match client IP %s", host, rhost), http.StatusUnauthorized)
 		return
 	}
+
 	newRelay.uri = uri
-	newRelay.Location = getLocation(uri.Host)

 	for _, current := range permanentRelays {
 		if current.uri.Host == newRelay.uri.Host {
 			if debug {
 				log.Println("Asked to add a relay", newRelay, "which exists in permanent list")
 			}
-			http.Error(w, "Invalid request", 500)
+			http.Error(w, "Invalid request", http.StatusBadRequest)
 			return
 		}
 	}
@@ -352,78 +443,105 @@ func handlePostRequest(w http.ResponseWriter, r *http.Request) {
 	reschan := make(chan result)

 	select {
-	case requests <- request{newRelay, uri, reschan}:
+	case requests <- request{&newRelay, reschan, prometheus.NewTimer(relayTestActionsSeconds.WithLabelValues("queue"))}:
 		result := <-reschan
 		if result.err != nil {
-			http.Error(w, result.err.Error(), 500)
+			relayTestsTotal.WithLabelValues("failed").Inc()
+			http.Error(w, result.err.Error(), http.StatusBadRequest)
 			return
 		}
+		relayTestsTotal.WithLabelValues("success").Inc()
 		w.Header().Set("Content-Type", "application/json; charset=utf-8")
 		json.NewEncoder(w).Encode(map[string]time.Duration{
 			"evictionIn": result.eviction,
 		})

 	default:
+		relayTestsTotal.WithLabelValues("dropped").Inc()
 		if debug {
 			log.Println("Dropping request")
 		}
-		w.WriteHeader(429)
+		w.WriteHeader(httpStatusEnhanceYourCalm)
 	}
 }

 func requestProcessor() {
 	for request := range requests {
-		if debug {
-			log.Println("Request for", request.relay)
-		}
-		if !client.TestRelay(request.uri, []tls.Certificate{testCert}, time.Second, 2*time.Second, 3) {
-			if debug {
-				log.Println("Test for relay", request.relay, "failed")
-			}
-			request.result <- result{fmt.Errorf("test failed"), 0}
-			continue
+		if request.queueTimer != nil {
+			request.queueTimer.ObserveDuration()
 		}

-		mut.Lock()
-		timer, ok := evictionTimers[request.relay.uri.Host]
-		if ok {
-			if debug {
-				log.Println("Stopping existing timer for", request.relay)
-			}
-			timer.Stop()
-		}
-
-		for i, current := range knownRelays {
-			if current.uri.Host == request.relay.uri.Host {
-				if debug {
-					log.Println("Relay", request.relay, "already exists")
-				}
-
-				// Evict the old entry anyway, as configuration might have changed.
-				last := len(knownRelays) - 1
-				knownRelays[i] = knownRelays[last]
-				knownRelays = knownRelays[:last]
-
-				goto found
-			}
-		}
-
-		if debug {
-			log.Println("Adding new relay", request.relay)
-		}
-
-	found:
-
-		knownRelays = append(knownRelays, request.relay)
-
-		evictionTimers[request.relay.uri.Host] = time.AfterFunc(evictionTime, evict(request.relay))
-		mut.Unlock()
-		request.result <- result{nil, evictionTime}
+		timer := prometheus.NewTimer(relayTestActionsSeconds.WithLabelValues("test"))
+		handleRelayTest(request)
+		timer.ObserveDuration()
 	}
-
 }

-func evict(relay relay) func() {
+func handleRelayTest(request request) {
+	if debug {
+		log.Println("Request for", request.relay)
+	}
+	if !client.TestRelay(context.TODO(), request.relay.uri, []tls.Certificate{testCert}, time.Second, 2*time.Second, 3) {
+		if debug {
+			log.Println("Test for relay", request.relay, "failed")
+		}
+		request.result <- result{fmt.Errorf("connection test failed"), 0}
+		return
+	}
+
+	stats := fetchStats(request.relay)
+	location := getLocation(request.relay.uri.Host)
+
+	mut.Lock()
+	if stats != nil {
+		updateMetrics(request.relay.uri.Host, *stats, location)
+	}
+	request.relay.Stats = stats
+	request.relay.StatsRetrieved = time.Now()
+	request.relay.Location = location
+
+	timer, ok := evictionTimers[request.relay.uri.Host]
+	if ok {
+		if debug {
+			log.Println("Stopping existing timer for", request.relay)
+		}
+		timer.Stop()
+	}
+
+	for i, current := range knownRelays {
+		if current.uri.Host == request.relay.uri.Host {
+			if debug {
+				log.Println("Relay", request.relay, "already exists")
+			}
+
+			// Evict the old entry anyway, as configuration might have changed.
+			last := len(knownRelays) - 1
+			knownRelays[i] = knownRelays[last]
+			knownRelays = knownRelays[:last]
+
+			goto found
+		}
+	}
+
+	if debug {
+		log.Println("Adding new relay", request.relay)
+	}
+
+found:
+
+	knownRelays = append(knownRelays, request.relay)
+	evictionTimers[request.relay.uri.Host] = time.AfterFunc(evictionTime, evict(request.relay))
+
+	mut.Unlock()
+
+	if err := saveRelays(knownRelaysFile, knownRelays); err != nil {
+		log.Println("Failed to write known relays: " + err.Error())
+	}
+
+	request.result <- result{nil, evictionTime}
+}
+
+func evict(relay *relay) func() {
 	return func() {
 		mut.Lock()
 		defer mut.Unlock()
@@ -438,6 +556,7 @@ func evict(relay relay) func() {
 				last := len(knownRelays) - 1
 				knownRelays[i] = knownRelays[last]
 				knownRelays = knownRelays[:last]
+				deleteMetrics(current.uri.Host)
 			}
 		}
 		delete(evictionTimers, relay.uri.Host)
@@ -445,13 +564,12 @@ func evict(relay relay) func() {
 }

 func limit(addr string, cache *lru.Cache, lock sync.RWMutex, intv time.Duration, burst int) bool {
-	host, _, err := net.SplitHostPort(addr)
-	if err != nil {
-		return false
+	if host, _, err := net.SplitHostPort(addr); err == nil {
+		addr = host
 	}

 	lock.RLock()
-	bkt, ok := cache.Get(host)
+	bkt, ok := cache.Get(addr)
 	lock.RUnlock()
 	if ok {
 		bkt := bkt.(*rate.Limiter)
@@ -461,18 +579,20 @@ func limit(addr string, cache *lru.Cache, lock sync.RWMutex, intv time.Duration,
 		}
 	} else {
 		lock.Lock()
-		cache.Add(host, rate.NewLimiter(rate.Every(intv), burst))
+		cache.Add(addr, rate.NewLimiter(rate.Every(intv), burst))
 		lock.Unlock()
 	}
 	return false
 }

-func loadPermanentRelays(file string) {
+func loadRelays(file string) []*relay {
 	content, err := ioutil.ReadFile(file)
 	if err != nil {
-		log.Fatal(err)
+		log.Println("Failed to load relays: " + err.Error())
+		return nil
 	}

+	var relays []*relay
 	for _, line := range strings.Split(string(content), "\n") {
 		if len(line) == 0 {
 			continue
@@ -481,21 +601,30 @@ func loadPermanentRelays(file string) {
 		uri, err := url.Parse(line)
 		if err != nil {
 			if debug {
-				log.Println("Skipping permanent relay", line, "due to parse error", err)
+				log.Println("Skipping relay", line, "due to parse error", err)
 			}
 			continue

 		}

-		permanentRelays = append(permanentRelays, relay{
+		relays = append(relays, &relay{
 			URL:      line,
 			Location: getLocation(uri.Host),
 			uri:      uri,
 		})
 		if debug {
-			log.Println("Adding permanent relay", line)
+			log.Println("Adding relay", line)
 		}
 	}
+	return relays
+}
+
+func saveRelays(file string, relays []*relay) error {
+	var content string
+	for _, relay := range relays {
+		content += relay.uri.String() + "\n"
+	}
+	return ioutil.WriteFile(file, []byte(content), 0777)
 }

 func createTestCertificate() tls.Certificate {
@@ -505,7 +634,7 @@ func createTestCertificate() tls.Certificate {
 	}

 	certFile, keyFile := filepath.Join(tmpDir, "cert.pem"), filepath.Join(tmpDir, "key.pem")
-	cert, err := tlsutil.NewCertificate(certFile, keyFile, "relaypoolsrv", 3072)
+	cert, err := tlsutil.NewCertificate(certFile, keyFile, "relaypoolsrv", 20*365)
 	if err != nil {
 		log.Fatalln("Failed to create test X509 key pair:", err)
 	}
@@ -514,6 +643,8 @@ func createTestCertificate() tls.Certificate {
 }

 func getLocation(host string) location {
+	timer := prometheus.NewTimer(locationLookupSeconds)
+	defer timer.ObserveDuration()
 	db, err := geoip2.Open(geoipPath)
 	if err != nil {
 		return location{}
@@ -531,7 +662,24 @@ func getLocation(host string) location {
 	}

 	return location{
-		Latitude:  city.Location.Latitude,
 		Longitude: city.Location.Longitude,
+		Latitude:  city.Location.Latitude,
+		City:      city.City.Names["en"],
+		Country:   city.Country.IsoCode,
+		Continent: city.Continent.Code,
 	}
 }
+
+type loggingResponseWriter struct {
+	http.ResponseWriter
+	statusCode int
+}
+
+func NewLoggingResponseWriter(w http.ResponseWriter) *loggingResponseWriter {
+	return &loggingResponseWriter{w, http.StatusOK}
+}
+
+func (lrw *loggingResponseWriter) WriteHeader(code int) {
+	lrw.statusCode = code
+	lrw.ResponseWriter.WriteHeader(code)
+}
--- a/cmd/strelaypoolsrv/stats.go
+++ b/cmd/strelaypoolsrv/stats.go
@@ -0,0 +1,259 @@
+// Copyright (C) 2018 Audrius Butkevicius and Contributors (see the CONTRIBUTORS file).
+
+package main
+
+import (
+	"encoding/json"
+	"net"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/syncthing/syncthing/lib/sync"
+)
+
+func init() {
+	processCollectorOpts := prometheus.ProcessCollectorOpts{
+		Namespace: "syncthing_relaypoolsrv",
+		PidFn: func() (int, error) {
+			return os.Getpid(), nil
+		},
+	}
+
+	prometheus.MustRegister(
+		prometheus.NewProcessCollector(processCollectorOpts),
+	)
+}
+
+var (
+	statusClient = http.Client{
+		Timeout: 5 * time.Second,
+	}
+
+	apiRequestsTotal   = makeCounter("api_requests_total", "Number of API requests.", "type", "result")
+	apiRequestsSeconds = makeSummary("api_requests_seconds", "Latency of API requests.", "type")
+
+	relayTestsTotal         = makeCounter("tests_total", "Number of relay tests.", "result")
+	relayTestActionsSeconds = makeSummary("test_actions_seconds", "Latency of relay test actions.", "type")
+
+	locationLookupSeconds = makeSummary("location_lookup_seconds", "Latency of location lookups.").WithLabelValues()
+
+	metricsRequestsSeconds = makeSummary("metrics_requests_seconds", "Latency of metric requests.").WithLabelValues()
+	scrapeSeconds          = makeSummary("relay_scrape_seconds", "Latency of metric scrapes from remote relays.", "result")
+
+	relayUptime             = makeGauge("relay_uptime", "Uptime of relay", "relay")
+	relayPendingSessionKeys = makeGauge("relay_pending_session_keys", "Number of pending session keys (two keys per session, one per each side of the connection)", "relay")
+	relayActiveSessions     = makeGauge("relay_active_sessions", "Number of sessions that are happening, a session contains two parties", "relay")
+	relayConnections        = makeGauge("relay_connections", "Number of devices connected to the relay", "relay")
+	relayProxies            = makeGauge("relay_proxies", "Number of active proxy routines sending data between peers (two proxies per session, one for each way)", "relay")
+	relayBytesProxied       = makeGauge("relay_bytes_proxied", "Number of bytes proxied by the relay", "relay")
+	relayGoRoutines         = makeGauge("relay_go_routines", "Number of Go routines in the process", "relay")
+	relaySessionRate        = makeGauge("relay_session_rate", "Rate applied per session", "relay")
+	relayGlobalRate         = makeGauge("relay_global_rate", "Global rate applied on the whole relay", "relay")
+	relayBuildInfo          = makeGauge("relay_build_info", "Build information about a relay", "relay", "go_version", "go_os", "go_arch")
+	relayLocationInfo       = makeGauge("relay_location_info", "Location information about a relay", "relay", "city", "country", "continent")
+
+	lastStats = make(map[string]stats)
+)
+
+func makeGauge(name string, help string, labels ...string) *prometheus.GaugeVec {
+	gauge := prometheus.NewGaugeVec(
+		prometheus.GaugeOpts{
+			Namespace: "syncthing",
+			Subsystem: "relaypoolsrv",
+			Name:      name,
+			Help:      help,
+		},
+		labels,
+	)
+	prometheus.MustRegister(gauge)
+	return gauge
+}
+
+func makeSummary(name string, help string, labels ...string) *prometheus.SummaryVec {
+	summary := prometheus.NewSummaryVec(
+		prometheus.SummaryOpts{
+			Namespace:  "syncthing",
+			Subsystem:  "relaypoolsrv",
+			Name:       name,
+			Help:       help,
+			Objectives: map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
+		},
+		labels,
+	)
+	prometheus.MustRegister(summary)
+	return summary
+}
+
+func makeCounter(name string, help string, labels ...string) *prometheus.CounterVec {
+	counter := prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: "syncthing",
+			Subsystem: "relaypoolsrv",
+			Name:      name,
+			Help:      help,
+		},
+		labels,
+	)
+	prometheus.MustRegister(counter)
+	return counter
+}
+
+func statsRefresher(interval time.Duration) {
+	ticker := time.NewTicker(interval)
+	for range ticker.C {
+		refreshStats()
+	}
+}
+
+type statsFetchResult struct {
+	relay *relay
+	stats *stats
+}
+
+func refreshStats() {
+	mut.RLock()
+	relays := append(permanentRelays, knownRelays...)
+	mut.RUnlock()
+
+	now := time.Now()
+	wg := sync.NewWaitGroup()
+
+	results := make(chan statsFetchResult, len(relays))
+	for _, rel := range relays {
+		wg.Add(1)
+		go func(rel *relay) {
+			t0 := time.Now()
+			stats := fetchStats(rel)
+			duration := time.Since(t0).Seconds()
+			result := "success"
+			if stats == nil {
+				result = "failed"
+			}
+			scrapeSeconds.WithLabelValues(result).Observe(duration)
+
+			results <- statsFetchResult{
+				relay: rel,
+				stats: fetchStats(rel),
+			}
+			wg.Done()
+		}(rel)
+	}
+
+	wg.Wait()
+	close(results)
+
+	mut.Lock()
+	relayBuildInfo.Reset()
+	relayLocationInfo.Reset()
+	for result := range results {
+		result.relay.StatsRetrieved = now
+		result.relay.Stats = result.stats
+		if result.stats == nil {
+			deleteMetrics(result.relay.uri.Host)
+		} else {
+			updateMetrics(result.relay.uri.Host, *result.stats, result.relay.Location)
+		}
+	}
+	mut.Unlock()
+}
+
+func fetchStats(relay *relay) *stats {
+	statusAddr := relay.uri.Query().Get("statusAddr")
+	if statusAddr == "" {
+		statusAddr = ":22070"
+	}
+
+	statusHost, statusPort, err := net.SplitHostPort(statusAddr)
+	if err != nil {
+		return nil
+	}
+
+	if statusHost == "" {
+		if host, _, err := net.SplitHostPort(relay.uri.Host); err != nil {
+			return nil
+		} else {
+			statusHost = host
+		}
+	}
+
+	url := "http://" + net.JoinHostPort(statusHost, statusPort) + "/status"
+
+	response, err := statusClient.Get(url)
+	if err != nil {
+		return nil
+	}
+
+	var stats stats
+
+	if json.NewDecoder(response.Body).Decode(&stats); err != nil {
+		return nil
+	}
+	return &stats
+}
+
+func updateMetrics(host string, stats stats, location location) {
+	if stats.GoVersion != "" || stats.GoOS != "" || stats.GoArch != "" {
+		relayBuildInfo.WithLabelValues(host, stats.GoVersion, stats.GoOS, stats.GoArch).Add(1)
+	}
+	if location.City != "" || location.Country != "" || location.Continent != "" {
+		relayLocationInfo.WithLabelValues(host, location.City, location.Country, location.Continent).Add(1)
+	}
+
+	if lastStat, ok := lastStats[host]; ok {
+		stats = mergeStats(stats, lastStat)
+	}
+
+	relayUptime.WithLabelValues(host).Set(float64(stats.UptimeSeconds))
+	relayPendingSessionKeys.WithLabelValues(host).Set(float64(stats.PendingSessionKeys))
+	relayActiveSessions.WithLabelValues(host).Set(float64(stats.ActiveSessions))
+	relayConnections.WithLabelValues(host).Set(float64(stats.Connections))
+	relayProxies.WithLabelValues(host).Set(float64(stats.Proxies))
+	relayBytesProxied.WithLabelValues(host).Set(float64(stats.BytesProxied))
+	relayGoRoutines.WithLabelValues(host).Set(float64(stats.GoRoutines))
+	relaySessionRate.WithLabelValues(host).Set(float64(stats.Options.SessionRate))
+	relayGlobalRate.WithLabelValues(host).Set(float64(stats.Options.GlobalRate))
+	lastStats[host] = stats
+}
+
+func deleteMetrics(host string) {
+	relayUptime.DeleteLabelValues(host)
+	relayPendingSessionKeys.DeleteLabelValues(host)
+	relayActiveSessions.DeleteLabelValues(host)
+	relayConnections.DeleteLabelValues(host)
+	relayProxies.DeleteLabelValues(host)
+	relayBytesProxied.DeleteLabelValues(host)
+	relayGoRoutines.DeleteLabelValues(host)
+	relaySessionRate.DeleteLabelValues(host)
+	relayGlobalRate.DeleteLabelValues(host)
+	delete(lastStats, host)
+}
+
+// Due to some unexplainable behaviour, some of the numbers sometimes travel slightly backwards (by less than 1%)
+// This happens between scrapes, which is 30s, so this can't be a race.
+// This causes prometheus to assume a "rate reset", hence causes phenomenal spikes.
+// One of the number that moves backwards is BytesProxied, which atomically increments a counter with numeric value
+// returned by net.Conn.Read(). I don't think that can return a negative value, so I have no idea what's going on.
+func mergeStats(new stats, old stats) stats {
+	new.UptimeSeconds = mergeValue(new.UptimeSeconds, old.UptimeSeconds)
+	new.PendingSessionKeys = mergeValue(new.PendingSessionKeys, old.PendingSessionKeys)
+	new.ActiveSessions = mergeValue(new.ActiveSessions, old.ActiveSessions)
+	new.Connections = mergeValue(new.Connections, old.Connections)
+	new.Proxies = mergeValue(new.Proxies, old.Proxies)
+	new.BytesProxied = mergeValue(new.BytesProxied, old.BytesProxied)
+	new.GoRoutines = mergeValue(new.GoRoutines, old.GoRoutines)
+	new.Options.SessionRate = mergeValue(new.Options.SessionRate, old.Options.SessionRate)
+	new.Options.GlobalRate = mergeValue(new.Options.GlobalRate, old.Options.GlobalRate)
+	return new
+}
+
+func mergeValue(new, old int) int {
+	if new >= old {
+		return new // normal increase
+	}
+	if float64(new) > 0.99*float64(old) {
+		return old // slight backward movement
+	}
+	return new // reset (relay restart)
+}
--- a/cmd/strelaypoolsrv/stats_test.go
+++ b/cmd/strelaypoolsrv/stats_test.go
@@ -0,0 +1,21 @@
+// Copyright (C) 2015 Audrius Butkevicius and Contributors (see the CONTRIBUTORS file).
+
+package main
+
+import (
+	"testing"
+)
+
+func TestMerge(t *testing.T) {
+	if mergeValue(1001, 1000) != 1001 {
+		t.Error("the computer says no")
+	}
+
+	if mergeValue(999, 1000) != 1000 {
+		t.Error("the computer says no")
+	}
+
+	if mergeValue(1, 1000) != 1 {
+		t.Error("the computer says no")
+	}
+}
--- a/cmd/strelaysrv/etc/firewall-ufw/strelaysrv
+++ b/cmd/strelaysrv/etc/firewall-ufw/strelaysrv
@@ -0,0 +1,9 @@
+[strelaysrv]
+title=Syncthing relay server
+description=Proxies traffic of syncthing client behind firewalls
+ports=22067/tcp
+
+[strelaysrv-metrics]
+title=Syncthing relay metrics
+description=Provides metrics about the syncthing relay server
+ports=22070/tcp
--- a/cmd/strelaysrv/etc/linux-systemd/default
+++ b/cmd/strelaysrv/etc/linux-systemd/default
@@ -0,0 +1,5 @@
+# Default settings for syncthing-relaysrv (strelaysrv).
+NAT=true
+
+## Add Options here:
+RELAYSRV_OPTS=
--- a/cmd/strelaysrv/etc/linux-systemd/strelaysrv.service
+++ b/cmd/strelaysrv/etc/linux-systemd/strelaysrv.service
@@ -1,17 +1,25 @@
 [Unit]
-Description=Syncthing relay server
+Description=Syncthing Relay Server
 After=network.target
+Documentation=man:strelaysrv(1)

 [Service]
-User=strelaysrv
-Group=strelaysrv
-ExecStart=/usr/bin/strelaysrv
-WorkingDirectory=/var/lib/strelaysrv
+WorkingDirectory=/var/lib/syncthing-relaysrv
+EnvironmentFile=/etc/default/syncthing-relaysrv
+ExecStart=/usr/bin/strelaysrv -nat=${NAT} $RELAYSRV_OPTS

-PrivateTmp=true
-ProtectSystem=full
-ProtectHome=true
+# Hardening
+User=syncthing-relaysrv
+Group=syncthing
+ProtectSystem=strict
+ReadWritePaths=/var/lib/syncthing-relaysrv
 NoNewPrivileges=true
+PrivateTmp=true
+PrivateDevices=true
+ProtectHome=true
+SystemCallArchitectures=native
+MemoryDenyWriteExecute=true

 [Install]
 WantedBy=multi-user.target
+Alias=syncthing-relaysrv.service
--- a/cmd/strelaysrv/main.go
+++ b/cmd/strelaysrv/main.go
@@ -14,12 +14,13 @@ import (
 	"os/signal"
 	"path/filepath"
 	"runtime"
-	"strconv"
 	"strings"
 	"sync/atomic"
 	"syscall"
 	"time"

+	"github.com/syncthing/syncthing/lib/build"
+	"github.com/syncthing/syncthing/lib/events"
 	"github.com/syncthing/syncthing/lib/osutil"
 	"github.com/syncthing/syncthing/lib/relay/protocol"
 	"github.com/syncthing/syncthing/lib/tlsutil"
@@ -33,24 +34,6 @@ import (
 	syncthingprotocol "github.com/syncthing/syncthing/lib/protocol"
 )

-var (
-	Version    string
-	BuildStamp string
-	BuildUser  string
-	BuildHost  string
-
-	BuildDate   time.Time
-	LongVersion string
-)
-
-func init() {
-	stamp, _ := strconv.Atoi(BuildStamp)
-	BuildDate = time.Unix(int64(stamp), 0)
-
-	date := BuildDate.UTC().Format("2006-01-02 15:04:05 MST")
-	LongVersion = fmt.Sprintf(`strelaysrv %s (%s %s-%s) %s@%s %s`, Version, runtime.Version(), runtime.GOOS, runtime.GOARCH, BuildUser, BuildHost, date)
-}
-
 var (
 	listen string
 	debug  bool
@@ -86,6 +69,12 @@ var (
 	pprofEnabled bool
 )

+// httpClient is the HTTP client we use for outbound requests. It has a
+// timeout and may get further options set during initialization.
+var httpClient = &http.Client{
+	Timeout: 30 * time.Second,
+}
+
 func main() {
 	log.SetFlags(log.Lshortfile | log.LstdFlags)

@@ -110,8 +99,14 @@ func main() {
 	flag.IntVar(&natTimeout, "nat-timeout", 10, "NAT discovery timeout in seconds")
 	flag.BoolVar(&pprofEnabled, "pprof", false, "Enable the built in profiling on the status server")
 	flag.IntVar(&networkBufferSize, "network-buffer", 2048, "Network buffer size (two of these per proxied connection)")
+	showVersion := flag.Bool("version", false, "Show version")
 	flag.Parse()

+	if *showVersion {
+		fmt.Println(build.LongVersion)
+		return
+	}
+
 	if extAddress == "" {
 		extAddress = listen
 	}
@@ -129,18 +124,18 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
+
 	if laddr.IP != nil && !laddr.IP.IsUnspecified() {
+		// We bind to a specific address. Our outgoing HTTP requests should
+		// also come from that address.
 		laddr.Port = 0
-		transport, ok := http.DefaultTransport.(*http.Transport)
-		if ok {
-			transport.Dial = (&net.Dialer{
-				Timeout:   30 * time.Second,
-				LocalAddr: laddr,
-			}).Dial
+		boundDialer := &net.Dialer{LocalAddr: laddr}
+		httpClient.Transport = &http.Transport{
+			DialContext: boundDialer.DialContext,
 		}
 	}

-	log.Println(LongVersion)
+	log.Println(build.LongVersion)

 	maxDescriptors, err := osutil.MaximizeOpenFileLimit()
 	if maxDescriptors > 0 {
@@ -160,7 +155,7 @@ func main() {
 	cert, err := tls.LoadX509KeyPair(certFile, keyFile)
 	if err != nil {
 		log.Println("Failed to load keypair. Generating one, this might take a while...")
-		cert, err = tlsutil.NewCertificate(certFile, keyFile, "strelaysrv", 3072)
+		cert, err = tlsutil.NewCertificate(certFile, keyFile, "strelaysrv", 20*365)
 		if err != nil {
 			log.Fatalln("Failed to generate X509 key pair:", err)
 		}
@@ -188,7 +183,7 @@ func main() {
 		log.Println("ID:", id)
 	}

-	wrapper := config.Wrap("config", config.New(id))
+	wrapper := config.Wrap("config", config.New(id), events.NoopLogger)
 	wrapper.SetOptions(config.OptionsConfiguration{
 		NATLeaseM:   natLease,
 		NATRenewalM: natRenewal,
--- a/cmd/strelaysrv/pool.go
+++ b/cmd/strelaysrv/pool.go
@@ -7,7 +7,6 @@ import (
 	"encoding/json"
 	"io/ioutil"
 	"log"
-	"net/http"
 	"net/url"
 	"time"
 )
@@ -27,7 +26,7 @@ func poolHandler(pool string, uri *url.URL, mapping mapping) {
 			uriCopy.String(),
 		})

-		resp, err := http.Post(pool, "application/json", &b)
+		resp, err := httpClient.Post(pool, "application/json", &b)
 		if err != nil {
 			log.Println("Error joining pool", pool, err)
 		} else if resp.StatusCode == 500 {
--- a/cmd/strelaysrv/scripts/preinst
+++ b/cmd/strelaysrv/scripts/preinst
@@ -0,0 +1,4 @@
+#!/bin/bash
+
+addgroup --system syncthing
+adduser --system --home /var/lib/syncthing-relaysrv --ingroup syncthing syncthing-relaysrv
--- a/cmd/strelaysrv/session.go
+++ b/cmd/strelaysrv/session.go
@@ -22,7 +22,7 @@ import (
 var (
 	sessionMut      = sync.RWMutex{}
 	activeSessions  = make([]*session, 0)
-	pendingSessions = make(map[string]*session, 0)
+	pendingSessions = make(map[string]*session)
 	numProxies      int64
 	bytesProxied    int64
 )
--- a/cmd/strelaysrv/status.go
+++ b/cmd/strelaysrv/status.go
@@ -10,6 +10,8 @@ import (
 	"runtime"
 	"sync/atomic"
 	"time"
+
+	"github.com/syncthing/syncthing/lib/build"
 )

 var rc *rateCalculator
@@ -40,6 +42,10 @@ func getStatus(w http.ResponseWriter, r *http.Request) {

 	sessionMut.Lock()
 	// This can potentially be double the number of pending sessions, as each session has two keys, one for each side.
+	status["version"] = build.Version
+	status["buildHost"] = build.Host
+	status["buildUser"] = build.User
+	status["buildDate"] = build.Date
 	status["startTime"] = rc.startTime
 	status["uptimeSeconds"] = time.Since(rc.startTime) / time.Second
 	status["numPendingSessionKeys"] = len(pendingSessions)
@@ -82,9 +88,9 @@ func getStatus(w http.ResponseWriter, r *http.Request) {
 }

 type rateCalculator struct {
+	counter   *int64 // atomic, must remain 64-bit aligned
 	rates     []int64
 	prev      int64
-	counter   *int64
 	startTime time.Time
 }

--- a/cmd/strelaysrv/testutil/main.go
+++ b/cmd/strelaysrv/testutil/main.go
@@ -4,6 +4,7 @@ package main

 import (
 	"bufio"
+	"context"
 	"crypto/tls"
 	"flag"
 	"log"
@@ -19,6 +20,8 @@ import (
 )

 func main() {
+	ctx := context.Background()
+
 	log.SetOutput(os.Stdout)
 	log.SetFlags(log.LstdFlags | log.Lshortfile)

@@ -76,7 +79,7 @@ func main() {
 		}()

 		for {
-			conn, err := client.JoinSession(<-recv)
+			conn, err := client.JoinSession(ctx, <-recv)
 			if err != nil {
 				log.Fatalln("Failed to join", err)
 			}
@@ -90,13 +93,13 @@ func main() {
 			log.Fatal(err)
 		}

-		invite, err := client.GetInvitationFromRelay(uri, id, []tls.Certificate{cert}, 10*time.Second)
+		invite, err := client.GetInvitationFromRelay(ctx, uri, id, []tls.Certificate{cert}, 10*time.Second)
 		if err != nil {
 			log.Fatal(err)
 		}

 		log.Println("Received invitation", invite)
-		conn, err := client.JoinSession(invite)
+		conn, err := client.JoinSession(ctx, invite)
 		if err != nil {
 			log.Fatalln("Failed to join", err)
 		}
@@ -104,7 +107,7 @@ func main() {
 		connectToStdio(stdin, conn)
 		log.Println("Finished", conn.RemoteAddr(), conn.LocalAddr())
 	} else if test {
-		if client.TestRelay(uri, []tls.Certificate{cert}, time.Second, 2*time.Second, 4) {
+		if client.TestRelay(ctx, uri, []tls.Certificate{cert}, time.Second, 2*time.Second, 4) {
 			log.Println("OK")
 		} else {
 			log.Println("FAIL")
--- a/cmd/stupgrades/main.go
+++ b/cmd/stupgrades/main.go
@@ -0,0 +1,57 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"encoding/json"
+	"flag"
+	"os"
+	"sort"
+
+	"github.com/syncthing/syncthing/lib/upgrade"
+)
+
+const defaultURL = "https://api.github.com/repos/syncthing/syncthing/releases?per_page=25"
+
+func main() {
+	url := flag.String("u", defaultURL, "GitHub releases url")
+	flag.Parse()
+
+	rels := upgrade.FetchLatestReleases(*url, "")
+	if rels == nil {
+		// An error was already logged
+		os.Exit(1)
+	}
+
+	sort.Sort(upgrade.SortByRelease(rels))
+	rels = filterForLatest(rels)
+
+	if err := json.NewEncoder(os.Stdout).Encode(rels); err != nil {
+		os.Exit(1)
+	}
+}
+
+// filterForLatest returns the latest stable and prerelease only. If the
+// stable version is newer (comes first in the list) there is no need to go
+// looking for a prerelease at all.
+func filterForLatest(rels []upgrade.Release) []upgrade.Release {
+	var filtered []upgrade.Release
+	var havePre bool
+	for _, rel := range rels {
+		if !rel.Prerelease {
+			// We found a stable version, we're good now.
+			filtered = append(filtered, rel)
+			break
+		}
+		if rel.Prerelease && !havePre {
+			// We remember the first prerelease we find.
+			filtered = append(filtered, rel)
+			havePre = true
+		}
+	}
+	return filtered
+}
--- a/cmd/syncthing/auditservice.go
+++ b/cmd/syncthing/auditservice.go
@@ -1,69 +0,0 @@
-// Copyright (C) 2015 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-package main
-
-import (
-	"encoding/json"
-	"io"
-
-	"github.com/syncthing/syncthing/lib/events"
-)
-
-// The auditService subscribes to events and writes these in JSON format, one
-// event per line, to the specified writer.
-type auditService struct {
-	w       io.Writer     // audit destination
-	stop    chan struct{} // signals time to stop
-	started chan struct{} // signals startup complete
-	stopped chan struct{} // signals stop complete
-}
-
-func newAuditService(w io.Writer) *auditService {
-	return &auditService{
-		w:       w,
-		stop:    make(chan struct{}),
-		started: make(chan struct{}),
-		stopped: make(chan struct{}),
-	}
-}
-
-// Serve runs the audit service.
-func (s *auditService) Serve() {
-	defer close(s.stopped)
-	sub := events.Default.Subscribe(events.AllEvents)
-	defer events.Default.Unsubscribe(sub)
-	enc := json.NewEncoder(s.w)
-
-	// We're ready to start processing events.
-	close(s.started)
-
-	for {
-		select {
-		case ev := <-sub.C():
-			enc.Encode(ev)
-		case <-s.stop:
-			return
-		}
-	}
-}
-
-// Stop stops the audit service.
-func (s *auditService) Stop() {
-	close(s.stop)
-}
-
-// WaitForStart returns once the audit service is ready to receive events, or
-// immediately if it's already running.
-func (s *auditService) WaitForStart() {
-	<-s.started
-}
-
-// WaitForStop returns once the audit service has stopped.
-// (Needed by the tests.)
-func (s *auditService) WaitForStop() {
-	<-s.stopped
-}
--- a/cmd/syncthing/blockprof.go
+++ b/cmd/syncthing/blockprof.go
@@ -22,11 +22,15 @@ func init() {
 			panic("Couldn't find block profiler")
 		}
 		l.Debugln("Starting block profiling")
-		go saveBlockingProfiles(profiler)
+		go func() {
+			err := saveBlockingProfiles(profiler) // Only returns on error
+			l.Warnln("Block profiler failed:", err)
+			panic("Block profiler failed")
+		}()
 	}
 }

-func saveBlockingProfiles(profiler *pprof.Profile) {
+func saveBlockingProfiles(profiler *pprof.Profile) error {
 	runtime.SetBlockProfileRate(1)

 	t0 := time.Now()
@@ -35,16 +39,16 @@ func saveBlockingProfiles(profiler *pprof.Profile) {

 		fd, err := os.Create(fmt.Sprintf("block-%05d-%07d.pprof", syscall.Getpid(), startms))
 		if err != nil {
-			panic(err)
+			return err
 		}
 		err = profiler.WriteTo(fd, 0)
 		if err != nil {
-			panic(err)
+			return err
 		}
 		err = fd.Close()
 		if err != nil {
-			panic(err)
+			return err
 		}
-
 	}
+	return nil
 }
--- a/cmd/syncthing/crash_reporting.go
+++ b/cmd/syncthing/crash_reporting.go
@@ -0,0 +1,152 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/syncthing/syncthing/lib/sha256"
+)
+
+const (
+	headRequestTimeout = 10 * time.Second
+	putRequestTimeout  = time.Minute
+)
+
+// uploadPanicLogs attempts to upload all the panic logs in the named
+// directory to the crash reporting server as urlBase. Uploads are attempted
+// with the newest log first.
+//
+// This can can block for a long time. The context can set a final deadline
+// for this.
+func uploadPanicLogs(ctx context.Context, urlBase, dir string) {
+	files, err := filepath.Glob(filepath.Join(dir, "panic-*.log"))
+	if err != nil {
+		l.Warnln("Failed to list panic logs:", err)
+		return
+	}
+
+	sort.Sort(sort.Reverse(sort.StringSlice(files)))
+	for _, file := range files {
+		if strings.Contains(file, ".reported.") {
+			// We've already sent this file. It'll be cleaned out at some
+			// point.
+			continue
+		}
+
+		if err := uploadPanicLog(ctx, urlBase, file); err != nil {
+			l.Warnln("Reporting crash:", err)
+		} else {
+			// Rename the log so we don't have to try to report it again. This
+			// succeeds, or it does not. There is no point complaining about it.
+			_ = os.Rename(file, strings.Replace(file, ".log", ".reported.log", 1))
+		}
+	}
+}
+
+// uploadPanicLog attempts to upload the named panic log to the crash
+// reporting server at urlBase. The panic ID is constructed as the sha256 of
+// the log contents. A HEAD request is made to see if the log has already
+// been reported. If not, a PUT is made with the log contents.
+func uploadPanicLog(ctx context.Context, urlBase, file string) error {
+	data, err := ioutil.ReadFile(file)
+	if err != nil {
+		return err
+	}
+
+	// Remove log lines, for privacy.
+	data = filterLogLines(data)
+
+	hash := fmt.Sprintf("%x", sha256.Sum256(data))
+	l.Infof("Reporting crash found in %s (report ID %s) ...\n", filepath.Base(file), hash[:8])
+
+	url := fmt.Sprintf("%s/%s", urlBase, hash)
+	headReq, err := http.NewRequest(http.MethodHead, url, nil)
+	if err != nil {
+		return err
+	}
+
+	// Set a reasonable timeout on the HEAD request
+	headCtx, headCancel := context.WithTimeout(ctx, headRequestTimeout)
+	defer headCancel()
+	headReq = headReq.WithContext(headCtx)
+
+	resp, err := http.DefaultClient.Do(headReq)
+	if err != nil {
+		return err
+	}
+	resp.Body.Close()
+	if resp.StatusCode == http.StatusOK {
+		// It's known, we're done
+		return nil
+	}
+
+	putReq, err := http.NewRequest(http.MethodPut, url, bytes.NewReader(data))
+	if err != nil {
+		return err
+	}
+
+	// Set a reasonable timeout on the PUT request
+	putCtx, putCancel := context.WithTimeout(ctx, putRequestTimeout)
+	defer putCancel()
+	putReq = putReq.WithContext(putCtx)
+
+	resp, err = http.DefaultClient.Do(putReq)
+	if err != nil {
+		return err
+	}
+	resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("upload: %s", resp.Status)
+	}
+
+	return nil
+}
+
+// filterLogLines returns the data without any log lines between the first
+// line and the panic trace. This is done in-place: the original data slice
+// is destroyed.
+func filterLogLines(data []byte) []byte {
+	filtered := data[:0]
+	matched := false
+	for _, line := range bytes.Split(data, []byte("\n")) {
+		switch {
+		case !matched && bytes.HasPrefix(line, []byte("Panic ")):
+			// This begins the panic trace, set the matched flag and append.
+			matched = true
+			fallthrough
+		case len(filtered) == 0 || matched:
+			// This is the first line or inside the panic trace.
+			if len(filtered) > 0 {
+				// We add the newline before rather than after because
+				// bytes.Split sees the \n as *separator* and not line
+				// ender, so ir will generate a last empty line that we
+				// don't really want. (We want to keep blank lines in the
+				// middle of the trace though.)
+				filtered = append(filtered, '\n')
+			}
+			// Remove the device ID prefix. The "plus two" stuff is because
+			// the line will look like "[foo] whatever" and the end variable
+			// will end up pointing at the ] and we want to step over that
+			// and the following space.
+			if end := bytes.Index(line, []byte("]")); end > 1 && end < len(line)-2 && bytes.HasPrefix(line, []byte("[")) {
+				line = line[end+2:]
+			}
+			filtered = append(filtered, line...)
+		}
+	}
+	return filtered
+}
--- a/cmd/syncthing/crash_reporting_test.go
+++ b/cmd/syncthing/crash_reporting_test.go
@@ -0,0 +1,37 @@
+// Copyright (C) 2019 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestFilterLogLines(t *testing.T) {
+	in := []byte(`[ABCD123] syncthing version whatever
+here is more log data
+and more
+...
+and some more
+yet more
+Panic detected at like right now
+here is panic data
+and yet more panic stuff
+`)
+
+	filtered := []byte(`syncthing version whatever
+Panic detected at like right now
+here is panic data
+and yet more panic stuff
+`)
+
+	result := filterLogLines(in)
+	if !bytes.Equal(result, filtered) {
+		t.Logf("%q\n", result)
+		t.Error("it should have been filtered")
+	}
+}
--- a/cmd/syncthing/debug.go
+++ b/cmd/syncthing/debug.go
@@ -7,22 +7,9 @@
 package main

 import (
-	"os"
-	"strings"
-
 	"github.com/syncthing/syncthing/lib/logger"
 )

 var (
-	l     = logger.DefaultLogger.NewFacility("main", "Main package")
-	httpl = logger.DefaultLogger.NewFacility("http", "REST API")
+	l = logger.DefaultLogger.NewFacility("main", "Main package")
 )
-
-func shouldDebugHTTP() bool {
-	return l.ShouldDebug("http")
-}
-
-func init() {
-	l.SetDebug("main", strings.Contains(os.Getenv("STTRACE"), "main") || os.Getenv("STTRACE") == "all")
-	l.SetDebug("http", strings.Contains(os.Getenv("STTRACE"), "http") || os.Getenv("STTRACE") == "all")
-}
--- a/cmd/syncthing/gui_auth.go
+++ b/cmd/syncthing/gui_auth.go
@@ -1,141 +0,0 @@
-// Copyright (C) 2014 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-package main
-
-import (
-	"bytes"
-	"encoding/base64"
-	"net/http"
-	"strings"
-	"time"
-
-	"github.com/syncthing/syncthing/lib/config"
-	"github.com/syncthing/syncthing/lib/events"
-	"github.com/syncthing/syncthing/lib/rand"
-	"github.com/syncthing/syncthing/lib/sync"
-	"golang.org/x/crypto/bcrypt"
-)
-
-var (
-	sessions    = make(map[string]bool)
-	sessionsMut = sync.NewMutex()
-)
-
-func emitLoginAttempt(success bool, username string) {
-	events.Default.Log(events.LoginAttempt, map[string]interface{}{
-		"success":  success,
-		"username": username,
-	})
-}
-
-func basicAuthAndSessionMiddleware(cookieName string, cfg config.GUIConfiguration, next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		if cfg.IsValidAPIKey(r.Header.Get("X-API-Key")) {
-			next.ServeHTTP(w, r)
-			return
-		}
-
-		cookie, err := r.Cookie(cookieName)
-		if err == nil && cookie != nil {
-			sessionsMut.Lock()
-			_, ok := sessions[cookie.Value]
-			sessionsMut.Unlock()
-			if ok {
-				next.ServeHTTP(w, r)
-				return
-			}
-		}
-
-		httpl.Debugln("Sessionless HTTP request with authentication; this is expensive.")
-
-		error := func() {
-			time.Sleep(time.Duration(rand.Intn(100)+100) * time.Millisecond)
-			w.Header().Set("WWW-Authenticate", "Basic realm=\"Authorization Required\"")
-			http.Error(w, "Not Authorized", http.StatusUnauthorized)
-		}
-
-		hdr := r.Header.Get("Authorization")
-		if !strings.HasPrefix(hdr, "Basic ") {
-			error()
-			return
-		}
-
-		hdr = hdr[6:]
-		bs, err := base64.StdEncoding.DecodeString(hdr)
-		if err != nil {
-			error()
-			return
-		}
-
-		fields := bytes.SplitN(bs, []byte(":"), 2)
-		if len(fields) != 2 {
-			error()
-			return
-		}
-
-		// Check if the username is correct, assuming it was sent as UTF-8
-		username := string(fields[0])
-		if username == cfg.User {
-			goto usernameOK
-		}
-
-		// ... check it again, converting it from assumed ISO-8859-1 to UTF-8
-		username = string(iso88591ToUTF8(fields[0]))
-		if username == cfg.User {
-			goto usernameOK
-		}
-
-		// Neither of the possible interpretations match the configured username
-		emitLoginAttempt(false, username)
-		error()
-		return
-
-	usernameOK:
-		// Check password as given (assumes UTF-8 encoding)
-		password := fields[1]
-		if err := bcrypt.CompareHashAndPassword([]byte(cfg.Password), password); err == nil {
-			goto passwordOK
-		}
-
-		// ... check it again, converting it from assumed ISO-8859-1 to UTF-8
-		password = iso88591ToUTF8(password)
-		if err := bcrypt.CompareHashAndPassword([]byte(cfg.Password), password); err == nil {
-			goto passwordOK
-		}
-
-		// Neither of the attempts to verify the password checked out
-		emitLoginAttempt(false, username)
-		error()
-		return
-
-	passwordOK:
-		sessionid := rand.String(32)
-		sessionsMut.Lock()
-		sessions[sessionid] = true
-		sessionsMut.Unlock()
-		http.SetCookie(w, &http.Cookie{
-			Name:   cookieName,
-			Value:  sessionid,
-			MaxAge: 0,
-		})
-
-		emitLoginAttempt(true, username)
-		next.ServeHTTP(w, r)
-	})
-}
-
-// Convert an ISO-8859-1 encoded byte string to UTF-8. Works by the
-// principle that ISO-8859-1 bytes are equivalent to unicode code points,
-// that a rune slice is a list of code points, and that stringifying a slice
-// of runes generates UTF-8 in Go.
-func iso88591ToUTF8(s []byte) []byte {
-	runes := make([]rune, len(s))
-	for i := range s {
-		runes[i] = rune(s[i])
-	}
-	return []byte(string(runes))
-}
--- a/cmd/syncthing/gui_csrf.go
+++ b/cmd/syncthing/gui_csrf.go
@@ -1,142 +0,0 @@
-// Copyright (C) 2014 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-package main
-
-import (
-	"bufio"
-	"fmt"
-	"net/http"
-	"os"
-	"strings"
-
-	"github.com/syncthing/syncthing/lib/config"
-	"github.com/syncthing/syncthing/lib/osutil"
-	"github.com/syncthing/syncthing/lib/rand"
-	"github.com/syncthing/syncthing/lib/sync"
-)
-
-// csrfTokens is a list of valid tokens. It is sorted so that the most
-// recently used token is first in the list. New tokens are added to the front
-// of the list (as it is the most recently used at that time). The list is
-// pruned to a maximum of maxCsrfTokens, throwing away the least recently used
-// tokens.
-var csrfTokens []string
-var csrfMut = sync.NewMutex()
-
-const maxCsrfTokens = 25
-
-// Check for CSRF token on /rest/ URLs. If a correct one is not given, reject
-// the request with 403. For / and /index.html, set a new CSRF cookie if none
-// is currently set.
-func csrfMiddleware(unique string, prefix string, cfg config.GUIConfiguration, next http.Handler) http.Handler {
-	loadCsrfTokens()
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		// Allow requests carrying a valid API key
-		if cfg.IsValidAPIKey(r.Header.Get("X-API-Key")) {
-			// Set the access-control-allow-origin header for CORS requests
-			// since a valid API key has been provided
-			w.Header().Add("Access-Control-Allow-Origin", "*")
-			next.ServeHTTP(w, r)
-			return
-		}
-
-		if strings.HasPrefix(r.URL.Path, "/rest/debug") {
-			// Debugging functions are only available when explicitly
-			// enabled, and can be accessed without a CSRF token
-			next.ServeHTTP(w, r)
-			return
-		}
-
-		// Allow requests for anything not under the protected path prefix,
-		// and set a CSRF cookie if there isn't already a valid one.
-		if !strings.HasPrefix(r.URL.Path, prefix) {
-			cookie, err := r.Cookie("CSRF-Token-" + unique)
-			if err != nil || !validCsrfToken(cookie.Value) {
-				httpl.Debugln("new CSRF cookie in response to request for", r.URL)
-				cookie = &http.Cookie{
-					Name:  "CSRF-Token-" + unique,
-					Value: newCsrfToken(),
-				}
-				http.SetCookie(w, cookie)
-			}
-			next.ServeHTTP(w, r)
-			return
-		}
-
-		// Verify the CSRF token
-		token := r.Header.Get("X-CSRF-Token-" + unique)
-		if !validCsrfToken(token) {
-			http.Error(w, "CSRF Error", 403)
-			return
-		}
-
-		next.ServeHTTP(w, r)
-	})
-}
-
-func validCsrfToken(token string) bool {
-	csrfMut.Lock()
-	defer csrfMut.Unlock()
-	for i, t := range csrfTokens {
-		if t == token {
-			if i > 0 {
-				// Move this token to the head of the list. Copy the tokens at
-				// the front one step to the right and then replace the token
-				// at the head.
-				copy(csrfTokens[1:], csrfTokens[:i+1])
-				csrfTokens[0] = token
-			}
-			return true
-		}
-	}
-	return false
-}
-
-func newCsrfToken() string {
-	token := rand.String(32)
-
-	csrfMut.Lock()
-	csrfTokens = append([]string{token}, csrfTokens...)
-	if len(csrfTokens) > maxCsrfTokens {
-		csrfTokens = csrfTokens[:maxCsrfTokens]
-	}
-	defer csrfMut.Unlock()
-
-	saveCsrfTokens()
-
-	return token
-}
-
-func saveCsrfTokens() {
-	// We're ignoring errors in here. It's not super critical and there's
-	// nothing relevant we can do about them anyway...
-
-	name := locations[locCsrfTokens]
-	f, err := osutil.CreateAtomic(name)
-	if err != nil {
-		return
-	}
-
-	for _, t := range csrfTokens {
-		fmt.Fprintln(f, t)
-	}
-
-	f.Close()
-}
-
-func loadCsrfTokens() {
-	f, err := os.Open(locations[locCsrfTokens])
-	if err != nil {
-		return
-	}
-	defer f.Close()
-
-	s := bufio.NewScanner(f)
-	for s.Scan() {
-		csrfTokens = append(csrfTokens, s.Text())
-	}
-}
--- a/cmd/syncthing/heapprof.go
+++ b/cmd/syncthing/heapprof.go
@@ -23,11 +23,15 @@ func init() {
 			rate = i
 		}
 		l.Debugln("Starting heap profiling")
-		go saveHeapProfiles(rate)
+		go func() {
+			err := saveHeapProfiles(rate) // Only returns on error
+			l.Warnln("Heap profiler failed:", err)
+			panic("Heap profiler failed")
+		}()
 	}
 }

-func saveHeapProfiles(rate int) {
+func saveHeapProfiles(rate int) error {
 	runtime.MemProfileRate = rate
 	var memstats, prevMemstats runtime.MemStats

@@ -38,21 +42,21 @@ func saveHeapProfiles(rate int) {
 		if memstats.HeapInuse > prevMemstats.HeapInuse {
 			fd, err := os.Create(name + ".tmp")
 			if err != nil {
-				panic(err)
+				return err
 			}
 			err = pprof.WriteHeapProfile(fd)
 			if err != nil {
-				panic(err)
+				return err
 			}
 			err = fd.Close()
 			if err != nil {
-				panic(err)
+				return err
 			}

-			_ = os.Remove(name) // Error deliberately ignored
+			os.Remove(name) // Error deliberately ignored
 			err = os.Rename(name+".tmp", name)
 			if err != nil {
-				panic(err)
+				return err
 			}

 			prevMemstats = memstats
--- a/cmd/syncthing/locations.go
+++ b/cmd/syncthing/locations.go
@@ -1,125 +0,0 @@
-// Copyright (C) 2015 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-package main
-
-import (
-	"os"
-	"path/filepath"
-	"runtime"
-	"strings"
-	"time"
-
-	"github.com/syncthing/syncthing/lib/fs"
-)
-
-type locationEnum string
-
-// Use strings as keys to make printout and serialization of the locations map
-// more meaningful.
-const (
-	locConfigFile    locationEnum = "config"
-	locCertFile                   = "certFile"
-	locKeyFile                    = "keyFile"
-	locHTTPSCertFile              = "httpsCertFile"
-	locHTTPSKeyFile               = "httpsKeyFile"
-	locDatabase                   = "database"
-	locLogFile                    = "logFile"
-	locCsrfTokens                 = "csrfTokens"
-	locPanicLog                   = "panicLog"
-	locAuditLog                   = "auditLog"
-	locGUIAssets                  = "GUIAssets"
-	locDefFolder                  = "defFolder"
-)
-
-// Platform dependent directories
-var baseDirs = map[string]string{
-	"config": defaultConfigDir(), // Overridden by -home flag
-	"home":   homeDir(),          // User's home directory, *not* -home flag
-}
-
-// Use the variables from baseDirs here
-var locations = map[locationEnum]string{
-	locConfigFile:    "${config}/config.xml",
-	locCertFile:      "${config}/cert.pem",
-	locKeyFile:       "${config}/key.pem",
-	locHTTPSCertFile: "${config}/https-cert.pem",
-	locHTTPSKeyFile:  "${config}/https-key.pem",
-	locDatabase:      "${config}/index-v0.14.0.db",
-	locLogFile:       "${config}/syncthing.log", // -logfile on Windows
-	locCsrfTokens:    "${config}/csrftokens.txt",
-	locPanicLog:      "${config}/panic-${timestamp}.log",
-	locAuditLog:      "${config}/audit-${timestamp}.log",
-	locGUIAssets:     "${config}/gui",
-	locDefFolder:     "${home}/Sync",
-}
-
-// expandLocations replaces the variables in the location map with actual
-// directory locations.
-func expandLocations() error {
-	for key, dir := range locations {
-		for varName, value := range baseDirs {
-			dir = strings.Replace(dir, "${"+varName+"}", value, -1)
-		}
-		var err error
-		dir, err = fs.ExpandTilde(dir)
-		if err != nil {
-			return err
-		}
-		locations[key] = dir
-	}
-	return nil
-}
-
-// defaultConfigDir returns the default configuration directory, as figured
-// out by various the environment variables present on each platform, or dies
-// trying.
-func defaultConfigDir() string {
-	switch runtime.GOOS {
-	case "windows":
-		if p := os.Getenv("LocalAppData"); p != "" {
-			return filepath.Join(p, "Syncthing")
-		}
-		return filepath.Join(os.Getenv("AppData"), "Syncthing")
-
-	case "darwin":
-		dir, err := fs.ExpandTilde("~/Library/Application Support/Syncthing")
-		if err != nil {
-			l.Fatalln(err)
-		}
-		return dir
-
-	default:
-		if xdgCfg := os.Getenv("XDG_CONFIG_HOME"); xdgCfg != "" {
-			return filepath.Join(xdgCfg, "syncthing")
-		}
-		dir, err := fs.ExpandTilde("~/.config/syncthing")
-		if err != nil {
-			l.Fatalln(err)
-		}
-		return dir
-	}
-}
-
-// homeDir returns the user's home directory, or dies trying.
-func homeDir() string {
-	home, err := fs.ExpandTilde("~")
-	if err != nil {
-		l.Fatalln(err)
-	}
-	return home
-}
-
-func timestampedLoc(key locationEnum) string {
-	// We take the roundtrip via "${timestamp}" instead of passing the path
-	// directly through time.Format() to avoid issues when the path we are
-	// expanding contains numbers; otherwise for example
-	// /home/user2006/.../panic-20060102-150405.log would get both instances of
-	// 2006 replaced by 2015...
-	tpl := locations[key]
-	now := time.Now().Format("20060102-150405")
-	return strings.Replace(tpl, "${timestamp}", now, -1)
-}
--- a/cmd/syncthing/main.go
+++ b/cmd/syncthing/main.go
--- a/cmd/syncthing/mocked_config_test.go
+++ b/cmd/syncthing/mocked_config_test.go
@@ -1,65 +0,0 @@
-// Copyright (C) 2016 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-package main
-
-import (
-	"github.com/syncthing/syncthing/lib/config"
-	"github.com/syncthing/syncthing/lib/protocol"
-	"github.com/syncthing/syncthing/lib/util"
-)
-
-type mockedConfig struct {
-	gui config.GUIConfiguration
-}
-
-func (c *mockedConfig) GUI() config.GUIConfiguration {
-	return c.gui
-}
-
-func (c *mockedConfig) ListenAddresses() []string {
-	return nil
-}
-
-func (c *mockedConfig) RawCopy() config.Configuration {
-	cfg := config.Configuration{}
-	util.SetDefaults(&cfg.Options)
-	return cfg
-}
-
-func (c *mockedConfig) Options() config.OptionsConfiguration {
-	return config.OptionsConfiguration{}
-}
-
-func (c *mockedConfig) Replace(cfg config.Configuration) (config.Waiter, error) {
-	return nil, nil
-}
-
-func (c *mockedConfig) Subscribe(cm config.Committer) {}
-
-func (c *mockedConfig) Folders() map[string]config.FolderConfiguration {
-	return nil
-}
-
-func (c *mockedConfig) Devices() map[protocol.DeviceID]config.DeviceConfiguration {
-	return nil
-}
-
-func (c *mockedConfig) SetDevice(config.DeviceConfiguration) (config.Waiter, error) {
-	return nil, nil
-}
-
-func (c *mockedConfig) SetDevices([]config.DeviceConfiguration) (config.Waiter, error) {
-	return nil, nil
-}
-
-func (c *mockedConfig) Save() error {
-	return nil
-}
-
-func (c *mockedConfig) RequiresRestart() bool {
-	return false
-}
--- a/cmd/syncthing/mocked_connections_test.go
+++ b/cmd/syncthing/mocked_connections_test.go
@@ -1,17 +0,0 @@
-// Copyright (C) 2016 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-package main
-
-type mockedConnections struct{}
-
-func (m *mockedConnections) Status() map[string]interface{} {
-	return nil
-}
-
-func (m *mockedConnections) NATType() string {
-	return ""
-}
--- a/cmd/syncthing/monitor.go
+++ b/cmd/syncthing/monitor.go
@@ -8,17 +8,24 @@ package main

 import (
 	"bufio"
+	"context"
+	"fmt"
 	"io"
 	"os"
 	"os/exec"
 	"os/signal"
+	"path/filepath"
 	"runtime"
 	"strings"
 	"syscall"
 	"time"

+	"github.com/syncthing/syncthing/lib/events"
+	"github.com/syncthing/syncthing/lib/locations"
 	"github.com/syncthing/syncthing/lib/osutil"
+	"github.com/syncthing/syncthing/lib/protocol"
 	"github.com/syncthing/syncthing/lib/sync"
+	"github.com/syncthing/syncthing/lib/syncthing"
 )

 var (
@@ -32,6 +39,8 @@ const (
 	loopThreshold         = 60 * time.Second
 	logFileAutoCloseDelay = 5 * time.Second
 	logFileMaxOpenTime    = time.Minute
+	panicUploadMaxWait    = 30 * time.Second
+	panicUploadNoticeWait = 10 * time.Second
 )

 func monitorMain(runtimeOptions RuntimeOptions) {
@@ -41,7 +50,15 @@ func monitorMain(runtimeOptions RuntimeOptions) {

 	logFile := runtimeOptions.logFile
 	if logFile != "-" {
-		var fileDst io.Writer = newAutoclosedFile(logFile, logFileAutoCloseDelay, logFileMaxOpenTime)
+		var fileDst io.Writer
+		if runtimeOptions.logMaxSize > 0 {
+			open := func(name string) (io.WriteCloser, error) {
+				return newAutoclosedFile(name, logFileAutoCloseDelay, logFileMaxOpenTime), nil
+			}
+			fileDst = newRotatedFile(logFile, open, int64(runtimeOptions.logMaxSize), runtimeOptions.logMaxFiles)
+		} else {
+			fileDst = newAutoclosedFile(logFile, logFileAutoCloseDelay, logFileMaxOpenTime)
+		}

 		if runtime.GOOS == "windows" {
 			// Translate line breaks to Windows standard
@@ -71,9 +88,11 @@ func monitorMain(runtimeOptions RuntimeOptions) {
 	childEnv := childEnv()
 	first := true
 	for {
+		maybeReportPanics()
+
 		if t := time.Since(restarts[0]); t < loopThreshold {
 			l.Warnf("%d restarts in %v; not retrying further", countRestarts, t)
-			os.Exit(exitError)
+			os.Exit(syncthing.ExitError.AsInt())
 		}

 		copy(restarts[0:], restarts[1:])
@@ -84,18 +103,19 @@ func monitorMain(runtimeOptions RuntimeOptions) {

 		stderr, err := cmd.StderrPipe()
 		if err != nil {
-			l.Fatalln("stderr:", err)
+			panic(err)
 		}

 		stdout, err := cmd.StdoutPipe()
 		if err != nil {
-			l.Fatalln("stdout:", err)
+			panic(err)
 		}

 		l.Infoln("Starting syncthing")
 		err = cmd.Start()
 		if err != nil {
-			l.Fatalln(err)
+			l.Warnln("Error starting the main Syncthing process:", err)
+			panic("Error starting the main Syncthing process")
 		}

 		stdoutMut.Lock()
@@ -127,7 +147,7 @@ func monitorMain(runtimeOptions RuntimeOptions) {
 		select {
 		case s := <-stopSign:
 			l.Infof("Signal %d received; exiting", s)
-			cmd.Process.Kill()
+			cmd.Process.Signal(sigTerm)
 			<-exit
 			return

@@ -141,17 +161,14 @@ func monitorMain(runtimeOptions RuntimeOptions) {
 				// Successful exit indicates an intentional shutdown
 				return
 			} else if exiterr, ok := err.(*exec.ExitError); ok {
-				if status, ok := exiterr.Sys().(syscall.WaitStatus); ok {
-					switch status.ExitStatus() {
-					case exitUpgrading:
-						// Restart the monitor process to release the .old
-						// binary as part of the upgrade process.
-						l.Infoln("Restarting monitor...")
-						if err = restartMonitor(args); err != nil {
-							l.Warnln("Restart:", err)
-						}
-						return
+				if exiterr.ExitCode() == syncthing.ExitUpgrade.AsInt() {
+					// Restart the monitor process to release the .old
+					// binary as part of the upgrade process.
+					l.Infoln("Restarting monitor...")
+					if err = restartMonitor(args); err != nil {
+						l.Warnln("Restart:", err)
 					}
+					return
 				}
 			}
 		}
@@ -172,6 +189,13 @@ func copyStderr(stderr io.Reader, dst io.Writer) {
 	br := bufio.NewReader(stderr)

 	var panicFd *os.File
+	defer func() {
+		if panicFd != nil {
+			_ = panicFd.Close()
+			maybeReportPanics()
+		}
+	}()
+
 	for {
 		line, err := br.ReadString('\n')
 		if err != nil {
@@ -198,7 +222,7 @@ func copyStderr(stderr io.Reader, dst io.Writer) {
 			}

 			if strings.HasPrefix(line, "panic:") || strings.HasPrefix(line, "fatal error:") {
-				panicFd, err = os.Create(timestampedLoc(locPanicLog))
+				panicFd, err = os.Create(locations.GetTimestamped(locations.PanicLog))
 				if err != nil {
 					l.Warnln("Create panic log:", err)
 					continue
@@ -303,6 +327,81 @@ func restartMonitorWindows(args []string) error {
 	return cmd.Start()
 }

+// rotatedFile keeps a set of rotating logs. There will be the base file plus up
+// to maxFiles rotated ones, each ~ maxSize bytes large.
+type rotatedFile struct {
+	name        string
+	create      createFn
+	maxSize     int64 // bytes
+	maxFiles    int
+	currentFile io.WriteCloser
+	currentSize int64
+}
+
+// the createFn should act equivalently to os.Create
+type createFn func(name string) (io.WriteCloser, error)
+
+func newRotatedFile(name string, create createFn, maxSize int64, maxFiles int) *rotatedFile {
+	return &rotatedFile{
+		name:     name,
+		create:   create,
+		maxSize:  maxSize,
+		maxFiles: maxFiles,
+	}
+}
+
+func (r *rotatedFile) Write(bs []byte) (int, error) {
+	// Check if we're about to exceed the max size, and if so close this
+	// file so we'll start on a new one.
+	if r.currentSize+int64(len(bs)) > r.maxSize {
+		r.currentFile.Close()
+		r.currentFile = nil
+		r.currentSize = 0
+	}
+
+	// If we have no current log, rotate old files out of the way and create
+	// a new one.
+	if r.currentFile == nil {
+		r.rotate()
+		fd, err := r.create(r.name)
+		if err != nil {
+			return 0, err
+		}
+		r.currentFile = fd
+	}
+
+	n, err := r.currentFile.Write(bs)
+	r.currentSize += int64(n)
+	return n, err
+}
+
+func (r *rotatedFile) rotate() {
+	// The files are named "name", "name.0", "name.1", ...
+	// "name.(r.maxFiles-1)". Increase the numbers on the
+	// suffixed ones.
+	for i := r.maxFiles - 1; i > 0; i-- {
+		from := numberedFile(r.name, i-1)
+		to := numberedFile(r.name, i)
+		err := os.Rename(from, to)
+		if err != nil && !os.IsNotExist(err) {
+			fmt.Println("LOG: Rotating logs:", err)
+		}
+	}
+
+	// Rename the base to base.0
+	err := os.Rename(r.name, numberedFile(r.name, 0))
+	if err != nil && !os.IsNotExist(err) {
+		fmt.Println("LOG: Rotating logs:", err)
+	}
+}
+
+// numberedFile adds the number between the file name and the extension.
+func numberedFile(name string, num int) string {
+	ext := filepath.Ext(name) // contains the dot
+	withoutExt := name[:len(name)-len(ext)]
+	return fmt.Sprintf("%s.%d%s", withoutExt, num, ext)
+}
+
 // An autoclosedFile is an io.WriteCloser that opens itself for appending on
 // Write() and closes itself after an interval of no writes (closeDelay) or
 // when the file has been open for too long (maxOpenTime). A call to Write()
@@ -418,10 +517,10 @@ func (f *autoclosedFile) closerLoop() {
 func childEnv() []string {
 	var env []string
 	for _, str := range os.Environ() {
-		if strings.HasPrefix("STNORESTART=", str) {
+		if strings.HasPrefix(str, "STNORESTART=") {
 			continue
 		}
-		if strings.HasPrefix("STMONITORED=", str) {
+		if strings.HasPrefix(str, "STMONITORED=") {
 			continue
 		}
 		env = append(env, str)
@@ -429,3 +528,39 @@ func childEnv() []string {
 	env = append(env, "STMONITORED=yes")
 	return env
 }
+
+// maybeReportPanics tries to figure out if crash reporting is on or off,
+// and reports any panics it can find if it's enabled. We spend at most
+// panicUploadMaxWait uploading panics...
+func maybeReportPanics() {
+	// Try to get a config to see if/where panics should be reported.
+	cfg, err := loadOrDefaultConfig(protocol.EmptyDeviceID, events.NoopLogger)
+	if err != nil {
+		l.Warnln("Couldn't load config; not reporting crash")
+		return
+	}
+
+	// Bail if we're not supposed to report panics.
+	opts := cfg.Options()
+	if !opts.CREnabled {
+		return
+	}
+
+	// Set up a timeout on the whole operation.
+	ctx, cancel := context.WithTimeout(context.Background(), panicUploadMaxWait)
+	defer cancel()
+
+	// Print a notice if the upload takes a long time.
+	go func() {
+		select {
+		case <-ctx.Done():
+			return
+		case <-time.After(panicUploadNoticeWait):
+			l.Warnln("Uploading crash reports is taking a while, please wait...")
+		}
+	}()
+
+	// Report the panics.
+	dir := locations.GetBaseDir(locations.ConfigBaseDir)
+	uploadPanicLogs(ctx, opts.CRURL, dir)
+}
--- a/cmd/syncthing/monitor_test.go
+++ b/cmd/syncthing/monitor_test.go
@@ -7,6 +7,7 @@
 package main

 import (
+	"io"
 	"io/ioutil"
 	"os"
 	"path/filepath"
@@ -14,6 +15,123 @@ import (
 	"time"
 )

+func TestRotatedFile(t *testing.T) {
+	// Verify that log rotation happens.
+
+	dir, err := ioutil.TempDir("", "syncthing")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.RemoveAll(dir)
+
+	open := func(name string) (io.WriteCloser, error) {
+		return os.Create(name)
+	}
+
+	logName := filepath.Join(dir, "log.txt")
+	testData := []byte("12345678\n")
+	maxSize := int64(len(testData) + len(testData)/2)
+
+	// We allow the log file plus two rotated copies.
+	rf := newRotatedFile(logName, open, maxSize, 2)
+
+	// Write some bytes.
+	if _, err := rf.Write(testData); err != nil {
+		t.Fatal(err)
+	}
+	// They should be in the log.
+	checkSize(t, logName, len(testData))
+	checkNotExist(t, logName+".0")
+
+	// Write some more bytes. We should rotate and write into a new file as the
+	// new bytes don't fit.
+	if _, err := rf.Write(testData); err != nil {
+		t.Fatal(err)
+	}
+	checkSize(t, logName, len(testData))
+	checkSize(t, numberedFile(logName, 0), len(testData))
+	checkNotExist(t, logName+".1")
+
+	// Write another byte. That should fit without causing an extra rotate.
+	_, _ = rf.Write([]byte{42})
+	checkSize(t, logName, len(testData)+1)
+	checkSize(t, numberedFile(logName, 0), len(testData))
+	checkNotExist(t, numberedFile(logName, 1))
+
+	// Write some more bytes. We should rotate and write into a new file as the
+	// new bytes don't fit.
+	if _, err := rf.Write(testData); err != nil {
+		t.Fatal(err)
+	}
+	checkSize(t, logName, len(testData))
+	checkSize(t, numberedFile(logName, 0), len(testData)+1) // the one we wrote extra to, now rotated
+	checkSize(t, numberedFile(logName, 1), len(testData))
+	checkNotExist(t, numberedFile(logName, 2))
+
+	// Write some more bytes. We should rotate and write into a new file as the
+	// new bytes don't fit.
+	if _, err := rf.Write(testData); err != nil {
+		t.Fatal(err)
+	}
+	checkSize(t, logName, len(testData))
+	checkSize(t, numberedFile(logName, 0), len(testData))
+	checkSize(t, numberedFile(logName, 1), len(testData)+1)
+	checkNotExist(t, numberedFile(logName, 2)) // exceeds maxFiles so deleted
+}
+
+func TestNumberedFile(t *testing.T) {
+	// Mostly just illustrates where the number ends up and makes sure it
+	// doesn't crash without an extension.
+
+	cases := []struct {
+		in  string
+		num int
+		out string
+	}{
+		{
+			in:  "syncthing.log",
+			num: 42,
+			out: "syncthing.42.log",
+		},
+		{
+			in:  filepath.Join("asdfasdf", "syncthing.log.txt"),
+			num: 42,
+			out: filepath.Join("asdfasdf", "syncthing.log.42.txt"),
+		},
+		{
+			in:  "syncthing-log",
+			num: 42,
+			out: "syncthing-log.42",
+		},
+	}
+
+	for _, tc := range cases {
+		res := numberedFile(tc.in, tc.num)
+		if res != tc.out {
+			t.Errorf("numberedFile(%q, %d) => %q, expected %q", tc.in, tc.num, res, tc.out)
+		}
+	}
+}
+
+func checkSize(t *testing.T, name string, size int) {
+	t.Helper()
+	info, err := os.Lstat(name)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if info.Size() != int64(size) {
+		t.Errorf("%s wrong size: %d != expected %d", name, info.Size(), size)
+	}
+}
+
+func checkNotExist(t *testing.T, name string) {
+	t.Helper()
+	_, err := os.Lstat(name)
+	if !os.IsNotExist(err) {
+		t.Errorf("%s should not exist", name)
+	}
+}
+
 func TestAutoClosedFile(t *testing.T) {
 	os.RemoveAll("_autoclose")
 	defer os.RemoveAll("_autoclose")
--- a/cmd/syncthing/perfstats_unix.go
+++ b/cmd/syncthing/perfstats_unix.go
@@ -38,7 +38,10 @@ func savePerfStats(file string) {

 	t0 := time.Now()
 	for t := range time.NewTicker(250 * time.Millisecond).C {
-		syscall.Getrusage(syscall.RUSAGE_SELF, &rusage)
+		if err := syscall.Getrusage(syscall.RUSAGE_SELF, &rusage); err != nil {
+			continue
+		}
+
 		curTime := time.Now().UnixNano()
 		timeDiff := curTime - prevTime
 		curUsage := rusage.Utime.Nano() + rusage.Stime.Nano()
--- a/cmd/syncthing/summaryservice.go
+++ b/cmd/syncthing/summaryservice.go
@@ -1,229 +0,0 @@
-// Copyright (C) 2015 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-package main
-
-import (
-	"time"
-
-	"github.com/syncthing/syncthing/lib/events"
-	"github.com/syncthing/syncthing/lib/protocol"
-	"github.com/syncthing/syncthing/lib/sync"
-	"github.com/thejerf/suture"
-)
-
-// The folderSummaryService adds summary information events (FolderSummary and
-// FolderCompletion) into the event stream at certain intervals.
-type folderSummaryService struct {
-	*suture.Supervisor
-
-	cfg       configIntf
-	model     modelIntf
-	stop      chan struct{}
-	immediate chan string
-
-	// For keeping track of folders to recalculate for
-	foldersMut sync.Mutex
-	folders    map[string]struct{}
-
-	// For keeping track of when the last event request on the API was
-	lastEventReq    time.Time
-	lastEventReqMut sync.Mutex
-}
-
-func newFolderSummaryService(cfg configIntf, m modelIntf) *folderSummaryService {
-	service := &folderSummaryService{
-		Supervisor:      suture.NewSimple("folderSummaryService"),
-		cfg:             cfg,
-		model:           m,
-		stop:            make(chan struct{}),
-		immediate:       make(chan string),
-		folders:         make(map[string]struct{}),
-		foldersMut:      sync.NewMutex(),
-		lastEventReqMut: sync.NewMutex(),
-	}
-
-	service.Add(serviceFunc(service.listenForUpdates))
-	service.Add(serviceFunc(service.calculateSummaries))
-
-	return service
-}
-
-func (c *folderSummaryService) Stop() {
-	c.Supervisor.Stop()
-	close(c.stop)
-}
-
-// listenForUpdates subscribes to the event bus and makes note of folders that
-// need their data recalculated.
-func (c *folderSummaryService) listenForUpdates() {
-	sub := events.Default.Subscribe(events.LocalIndexUpdated | events.RemoteIndexUpdated | events.StateChanged | events.RemoteDownloadProgress | events.DeviceConnected)
-	defer events.Default.Unsubscribe(sub)
-
-	for {
-		// This loop needs to be fast so we don't miss too many events.
-
-		select {
-		case ev := <-sub.C():
-			if ev.Type == events.DeviceConnected {
-				// When a device connects we schedule a refresh of all
-				// folders shared with that device.
-
-				data := ev.Data.(map[string]string)
-				deviceID, _ := protocol.DeviceIDFromString(data["id"])
-
-				c.foldersMut.Lock()
-			nextFolder:
-				for _, folder := range c.cfg.Folders() {
-					for _, dev := range folder.Devices {
-						if dev.DeviceID == deviceID {
-							c.folders[folder.ID] = struct{}{}
-							continue nextFolder
-						}
-					}
-				}
-				c.foldersMut.Unlock()
-
-				continue
-			}
-
-			// The other events all have a "folder" attribute that they
-			// affect. Whenever the local or remote index is updated for a
-			// given folder we make a note of it.
-
-			data := ev.Data.(map[string]interface{})
-			folder := data["folder"].(string)
-
-			switch ev.Type {
-			case events.StateChanged:
-				if data["to"].(string) == "idle" && data["from"].(string) == "syncing" {
-					// The folder changed to idle from syncing. We should do an
-					// immediate refresh to update the GUI. The send to
-					// c.immediate must be nonblocking so that we can continue
-					// handling events.
-
-					select {
-					case c.immediate <- folder:
-						c.foldersMut.Lock()
-						delete(c.folders, folder)
-						c.foldersMut.Unlock()
-
-					default:
-					}
-				}
-
-			default:
-				// This folder needs to be refreshed whenever we do the next
-				// refresh.
-
-				c.foldersMut.Lock()
-				c.folders[folder] = struct{}{}
-				c.foldersMut.Unlock()
-			}
-
-		case <-c.stop:
-			return
-		}
-	}
-}
-
-// calculateSummaries periodically recalculates folder summaries and
-// completion percentage, and sends the results on the event bus.
-func (c *folderSummaryService) calculateSummaries() {
-	const pumpInterval = 2 * time.Second
-	pump := time.NewTimer(pumpInterval)
-
-	for {
-		select {
-		case <-pump.C:
-			t0 := time.Now()
-			for _, folder := range c.foldersToHandle() {
-				c.sendSummary(folder)
-			}
-
-			// We don't want to spend all our time calculating summaries. Lets
-			// set an arbitrary limit at not spending more than about 30% of
-			// our time here...
-			wait := 2*time.Since(t0) + pumpInterval
-			pump.Reset(wait)
-
-		case folder := <-c.immediate:
-			c.sendSummary(folder)
-
-		case <-c.stop:
-			return
-		}
-	}
-}
-
-// foldersToHandle returns the list of folders needing a summary update, and
-// clears the list.
-func (c *folderSummaryService) foldersToHandle() []string {
-	// We only recalculate summaries if someone is listening to events
-	// (a request to /rest/events has been made within the last
-	// pingEventInterval).
-
-	c.lastEventReqMut.Lock()
-	last := c.lastEventReq
-	c.lastEventReqMut.Unlock()
-	if time.Since(last) > defaultEventTimeout {
-		return nil
-	}
-
-	c.foldersMut.Lock()
-	res := make([]string, 0, len(c.folders))
-	for folder := range c.folders {
-		res = append(res, folder)
-		delete(c.folders, folder)
-	}
-	c.foldersMut.Unlock()
-	return res
-}
-
-// sendSummary send the summary events for a single folder
-func (c *folderSummaryService) sendSummary(folder string) {
-	// The folder summary contains how many bytes, files etc
-	// are in the folder and how in sync we are.
-	data, err := folderSummary(c.cfg, c.model, folder)
-	if err != nil {
-		return
-	}
-	events.Default.Log(events.FolderSummary, map[string]interface{}{
-		"folder":  folder,
-		"summary": data,
-	})
-
-	for _, devCfg := range c.cfg.Folders()[folder].Devices {
-		if devCfg.DeviceID.Equals(myID) {
-			// We already know about ourselves.
-			continue
-		}
-		if _, ok := c.model.Connection(devCfg.DeviceID); !ok {
-			// We're not interested in disconnected devices.
-			continue
-		}
-
-		// Get completion percentage of this folder for the
-		// remote device.
-		comp := jsonCompletion(c.model.Completion(devCfg.DeviceID, folder))
-		comp["folder"] = folder
-		comp["device"] = devCfg.DeviceID.String()
-		events.Default.Log(events.FolderCompletion, comp)
-	}
-}
-
-func (c *folderSummaryService) gotEventRequest() {
-	c.lastEventReqMut.Lock()
-	c.lastEventReq = time.Now()
-	c.lastEventReqMut.Unlock()
-}
-
-// serviceFunc wraps a function to create a suture.Service without stop
-// functionality.
-type serviceFunc func()
-
-func (f serviceFunc) Serve() { f() }
-func (f serviceFunc) Stop()  {}
--- a/cmd/todos/main.go
+++ b/cmd/todos/main.go
@@ -1,39 +0,0 @@
-// Copyright (C) 2014 The Syncthing Authors.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at https://mozilla.org/MPL/2.0/.
-
-// +build ignore
-
-package main
-
-import (
-	"bytes"
-	"fmt"
-	"io"
-	"os"
-)
-
-func main() {
-	buf := make([]byte, 4096)
-	var err error
-	for err == nil {
-		n, err := io.ReadFull(os.Stdin, buf)
-		if n > 0 {
-			buf = buf[:n]
-			repl := bytes.Replace(buf, []byte("\n"), []byte("\r\n"), -1)
-			_, err = os.Stdout.Write(repl)
-			if err != nil {
-				fmt.Println(err)
-				os.Exit(1)
-			}
-		}
-		if err == io.EOF {
-			return
-		}
-		buf = buf[:cap(buf)]
-	}
-	fmt.Println(err)
-	os.Exit(1)
-}
--- a/cmd/uraggregate/main.go
+++ b/cmd/uraggregate/main.go
@@ -0,0 +1,330 @@
+// Copyright (C) 2018 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"database/sql"
+	"log"
+	"os"
+	"time"
+
+	_ "github.com/lib/pq"
+)
+
+var dbConn = getEnvDefault("UR_DB_URL", "postgres://user:password@localhost/ur?sslmode=disable")
+
+func getEnvDefault(key, def string) string {
+	if val := os.Getenv(key); val != "" {
+		return val
+	}
+	return def
+}
+
+func main() {
+	log.SetFlags(log.Ltime | log.Ldate)
+	log.SetOutput(os.Stdout)
+
+	db, err := sql.Open("postgres", dbConn)
+	if err != nil {
+		log.Fatalln("database:", err)
+	}
+	err = setupDB(db)
+	if err != nil {
+		log.Fatalln("database:", err)
+	}
+
+	for {
+		runAggregation(db)
+		// Sleep until one minute past next midnight
+		sleepUntilNext(24*time.Hour, 1*time.Minute)
+	}
+}
+
+func runAggregation(db *sql.DB) {
+	since := maxIndexedDay(db, "VersionSummary")
+	log.Println("Aggregating VersionSummary data since", since)
+	rows, err := aggregateVersionSummary(db, since)
+	if err != nil {
+		log.Fatalln("aggregate:", err)
+	}
+	log.Println("Inserted", rows, "rows")
+
+	log.Println("Aggregating UserMovement data")
+	rows, err = aggregateUserMovement(db)
+	if err != nil {
+		log.Fatalln("aggregate:", err)
+	}
+	log.Println("Inserted", rows, "rows")
+
+	log.Println("Aggregating Performance data")
+	since = maxIndexedDay(db, "Performance")
+	rows, err = aggregatePerformance(db, since)
+	if err != nil {
+		log.Fatalln("aggregate:", err)
+	}
+	log.Println("Inserted", rows, "rows")
+
+	log.Println("Aggregating BlockStats data")
+	since = maxIndexedDay(db, "BlockStats")
+	rows, err = aggregateBlockStats(db, since)
+	if err != nil {
+		log.Fatalln("aggregate:", err)
+	}
+	log.Println("Inserted", rows, "rows")
+}
+
+func sleepUntilNext(intv, margin time.Duration) {
+	now := time.Now().UTC()
+	next := now.Truncate(intv).Add(intv).Add(margin)
+	log.Println("Sleeping until", next)
+	time.Sleep(next.Sub(now))
+}
+
+func setupDB(db *sql.DB) error {
+	_, err := db.Exec(`CREATE TABLE IF NOT EXISTS VersionSummary (
+		Day TIMESTAMP NOT NULL,
+		Version VARCHAR(8) NOT NULL,
+		Count INTEGER NOT NULL
+	)`)
+	if err != nil {
+		return err
+	}
+
+	_, err = db.Exec(`CREATE TABLE IF NOT EXISTS UserMovement (
+		Day TIMESTAMP NOT NULL,
+		Added INTEGER NOT NULL,
+		Bounced INTEGER NOT NULL,
+		Removed INTEGER NOT NULL
+	)`)
+	if err != nil {
+		return err
+	}
+
+	_, err = db.Exec(`CREATE TABLE IF NOT EXISTS Performance (
+		Day TIMESTAMP NOT NULL,
+		TotFiles INTEGER NOT NULL,
+		TotMiB INTEGER NOT NULL,
+		SHA256Perf DOUBLE PRECISION NOT NULL,
+		MemorySize INTEGER NOT NULL,
+		MemoryUsageMiB INTEGER NOT NULL
+	)`)
+	if err != nil {
+		return err
+	}
+
+	_, err = db.Exec(`CREATE TABLE IF NOT EXISTS BlockStats (
+		Day TIMESTAMP NOT NULL,
+		Reports INTEGER NOT NULL,
+		Total INTEGER NOT NULL,
+		Renamed INTEGER NOT NULL,
+		Reused INTEGER NOT NULL,
+		Pulled INTEGER NOT NULL,
+		CopyOrigin INTEGER NOT NULL,
+		CopyOriginShifted INTEGER NOT NULL,
+		CopyElsewhere INTEGER NOT NULL
+	)`)
+	if err != nil {
+		return err
+	}
+
+	var t string
+
+	row := db.QueryRow(`SELECT 'UniqueDayVersionIndex'::regclass`)
+	if err := row.Scan(&t); err != nil {
+		_, err = db.Exec(`CREATE UNIQUE INDEX UniqueDayVersionIndex ON VersionSummary (Day, Version)`)
+	}
+
+	row = db.QueryRow(`SELECT 'VersionDayIndex'::regclass`)
+	if err := row.Scan(&t); err != nil {
+		_, err = db.Exec(`CREATE INDEX VersionDayIndex ON VersionSummary (Day)`)
+	}
+
+	row = db.QueryRow(`SELECT 'MovementDayIndex'::regclass`)
+	if err := row.Scan(&t); err != nil {
+		_, err = db.Exec(`CREATE INDEX MovementDayIndex ON UserMovement (Day)`)
+	}
+
+	row = db.QueryRow(`SELECT 'PerformanceDayIndex'::regclass`)
+	if err := row.Scan(&t); err != nil {
+		_, err = db.Exec(`CREATE INDEX PerformanceDayIndex ON Performance (Day)`)
+	}
+
+	row = db.QueryRow(`SELECT 'BlockStatsDayIndex'::regclass`)
+	if err := row.Scan(&t); err != nil {
+		_, err = db.Exec(`CREATE INDEX BlockStatsDayIndex ON BlockStats (Day)`)
+	}
+
+	return err
+}
+
+func maxIndexedDay(db *sql.DB, table string) time.Time {
+	var t time.Time
+	row := db.QueryRow("SELECT MAX(Day) FROM " + table)
+	err := row.Scan(&t)
+	if err != nil {
+		return time.Time{}
+	}
+	return t
+}
+
+func aggregateVersionSummary(db *sql.DB, since time.Time) (int64, error) {
+	res, err := db.Exec(`INSERT INTO VersionSummary (
+	SELECT
+		DATE_TRUNC('day', Received) AS Day,
+		SUBSTRING(Version FROM '^v\d.\d+') AS Ver,
+		COUNT(*) AS Count
+		FROM Reports
+		WHERE
+			DATE_TRUNC('day', Received) > $1
+			AND DATE_TRUNC('day', Received) < DATE_TRUNC('day', NOW())
+			AND Version like 'v_.%'
+		GROUP BY Day, Ver
+		);
+	`, since)
+	if err != nil {
+		return 0, err
+	}
+
+	return res.RowsAffected()
+}
+
+func aggregateUserMovement(db *sql.DB) (int64, error) {
+	rows, err := db.Query(`SELECT
+		DATE_TRUNC('day', Received) AS Day,
+		UniqueID
+		FROM Reports
+		WHERE
+			DATE_TRUNC('day', Received) < DATE_TRUNC('day', NOW())
+			AND Version like 'v_.%'
+		ORDER BY Day
+	`)
+	if err != nil {
+		return 0, err
+	}
+	defer rows.Close()
+
+	firstSeen := make(map[string]time.Time)
+	lastSeen := make(map[string]time.Time)
+	var minTs time.Time
+	minTs = minTs.In(time.UTC)
+
+	for rows.Next() {
+		var ts time.Time
+		var id string
+		if err := rows.Scan(&ts, &id); err != nil {
+			return 0, err
+		}
+
+		if minTs.IsZero() {
+			minTs = ts
+		}
+		if _, ok := firstSeen[id]; !ok {
+			firstSeen[id] = ts
+		}
+		lastSeen[id] = ts
+	}
+
+	type sumRow struct {
+		day     time.Time
+		added   int
+		removed int
+		bounced int
+	}
+	var sumRows []sumRow
+	for t := minTs; t.Before(time.Now().Truncate(24 * time.Hour)); t = t.AddDate(0, 0, 1) {
+		var added, removed, bounced int
+		old := t.Before(time.Now().AddDate(0, 0, -30))
+		for id, first := range firstSeen {
+			last := lastSeen[id]
+			if first.Equal(t) && last.Equal(t) && old {
+				bounced++
+				continue
+			}
+			if first.Equal(t) {
+				added++
+			}
+			if last == t && old {
+				removed++
+			}
+		}
+		sumRows = append(sumRows, sumRow{t, added, removed, bounced})
+	}
+
+	tx, err := db.Begin()
+	if err != nil {
+		return 0, err
+	}
+	if _, err := tx.Exec("DELETE FROM UserMovement"); err != nil {
+		tx.Rollback()
+		return 0, err
+	}
+	for _, r := range sumRows {
+		if _, err := tx.Exec("INSERT INTO UserMovement (Day, Added, Removed, Bounced) VALUES ($1, $2, $3, $4)", r.day, r.added, r.removed, r.bounced); err != nil {
+			tx.Rollback()
+			return 0, err
+		}
+	}
+
+	return int64(len(sumRows)), tx.Commit()
+}
+
+func aggregatePerformance(db *sql.DB, since time.Time) (int64, error) {
+	res, err := db.Exec(`INSERT INTO Performance (
+	SELECT
+		DATE_TRUNC('day', Received) AS Day,
+		AVG(TotFiles) As TotFiles,
+		AVG(TotMiB) As TotMiB,
+		AVG(SHA256Perf) As SHA256Perf,
+		AVG(MemorySize) As MemorySize,
+		AVG(MemoryUsageMiB) As MemoryUsageMiB
+		FROM Reports
+		WHERE
+			DATE_TRUNC('day', Received) > $1
+			AND DATE_TRUNC('day', Received) < DATE_TRUNC('day', NOW())
+			AND Version like 'v_.%'
+		GROUP BY Day
+		);
+	`, since)
+	if err != nil {
+		return 0, err
+	}
+
+	return res.RowsAffected()
+}
+
+func aggregateBlockStats(db *sql.DB, since time.Time) (int64, error) {
+	// Filter out anything prior 0.14.41 as that has sum aggregations which
+	// made no sense.
+	res, err := db.Exec(`INSERT INTO BlockStats (
+	SELECT
+		DATE_TRUNC('day', Received) AS Day,
+		COUNT(1) As Reports,
+		SUM(BlocksTotal) AS Total,
+		SUM(BlocksRenamed) AS Renamed,
+		SUM(BlocksReused) AS Reused,
+		SUM(BlocksPulled) AS Pulled,
+		SUM(BlocksCopyOrigin) AS CopyOrigin,
+		SUM(BlocksCopyOriginShifted) AS CopyOriginShifted,
+		SUM(BlocksCopyElsewhere) AS CopyElsewhere
+		FROM Reports
+		WHERE
+			DATE_TRUNC('day', Received) > $1
+			AND DATE_TRUNC('day', Received) < DATE_TRUNC('day', NOW())
+			AND ReportVersion = 3
+			AND Version like 'v_.%'
+			AND Version NOT LIKE 'v0.14.40%'
+			AND Version NOT LIKE 'v0.14.39%'
+			AND Version NOT LIKE 'v0.14.38%'
+		GROUP BY Day
+	);
+	`, since)
+	if err != nil {
+		return 0, err
+	}
+
+	return res.RowsAffected()
+}
--- a/cmd/ursrv/analytics.go
+++ b/cmd/ursrv/analytics.go
@@ -0,0 +1,240 @@
+// Copyright (C) 2018 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"regexp"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+type analytic struct {
+	Key        string
+	Count      int
+	Percentage float64
+	Items      []analytic `json:",omitempty"`
+}
+
+type analyticList []analytic
+
+func (l analyticList) Less(a, b int) bool {
+	if l[a].Key == "Others" {
+		return false
+	}
+	if l[b].Key == "Others" {
+		return true
+	}
+	return l[b].Count < l[a].Count // inverse
+}
+
+func (l analyticList) Swap(a, b int) {
+	l[a], l[b] = l[b], l[a]
+}
+
+func (l analyticList) Len() int {
+	return len(l)
+}
+
+// Returns a list of frequency analytics for a given list of strings.
+func analyticsFor(ss []string, cutoff int) []analytic {
+	m := make(map[string]int)
+	t := 0
+	for _, s := range ss {
+		m[s]++
+		t++
+	}
+
+	l := make([]analytic, 0, len(m))
+	for k, c := range m {
+		l = append(l, analytic{
+			Key:        k,
+			Count:      c,
+			Percentage: 100 * float64(c) / float64(t),
+		})
+	}
+
+	sort.Sort(analyticList(l))
+
+	if cutoff > 0 && len(l) > cutoff {
+		c := 0
+		for _, i := range l[cutoff:] {
+			c += i.Count
+		}
+		l = append(l[:cutoff], analytic{
+			Key:        "Others",
+			Count:      c,
+			Percentage: 100 * float64(c) / float64(t),
+		})
+	}
+
+	return l
+}
+
+// Find the points at which certain penetration levels are met
+func penetrationLevels(as []analytic, points []float64) []analytic {
+	sort.Slice(as, func(a, b int) bool {
+		return versionLess(as[b].Key, as[a].Key)
+	})
+
+	var res []analytic
+
+	idx := 0
+	sum := 0.0
+	for _, a := range as {
+		sum += a.Percentage
+		if sum >= points[idx] {
+			a.Count = int(points[idx])
+			a.Percentage = sum
+			res = append(res, a)
+			idx++
+			if idx == len(points) {
+				break
+			}
+		}
+	}
+	return res
+}
+
+func statsForInts(data []int) [4]float64 {
+	var res [4]float64
+	if len(data) == 0 {
+		return res
+	}
+
+	sort.Ints(data)
+	res[0] = float64(data[int(float64(len(data))*0.05)])
+	res[1] = float64(data[len(data)/2])
+	res[2] = float64(data[int(float64(len(data))*0.95)])
+	res[3] = float64(data[len(data)-1])
+	return res
+}
+
+func statsForFloats(data []float64) [4]float64 {
+	var res [4]float64
+	if len(data) == 0 {
+		return res
+	}
+
+	sort.Float64s(data)
+	res[0] = data[int(float64(len(data))*0.05)]
+	res[1] = data[len(data)/2]
+	res[2] = data[int(float64(len(data))*0.95)]
+	res[3] = data[len(data)-1]
+	return res
+}
+
+func group(by func(string) string, as []analytic, perGroup int) []analytic {
+	var res []analytic
+
+next:
+	for _, a := range as {
+		group := by(a.Key)
+		for i := range res {
+			if res[i].Key == group {
+				res[i].Count += a.Count
+				res[i].Percentage += a.Percentage
+				if len(res[i].Items) < perGroup {
+					res[i].Items = append(res[i].Items, a)
+				}
+				continue next
+			}
+		}
+		res = append(res, analytic{
+			Key:        group,
+			Count:      a.Count,
+			Percentage: a.Percentage,
+			Items:      []analytic{a},
+		})
+	}
+
+	sort.Sort(analyticList(res))
+	return res
+}
+
+func byVersion(s string) string {
+	parts := strings.Split(s, ".")
+	if len(parts) >= 2 {
+		return strings.Join(parts[:2], ".")
+	}
+	return s
+}
+
+func byPlatform(s string) string {
+	parts := strings.Split(s, "-")
+	if len(parts) >= 2 {
+		return parts[0]
+	}
+	return s
+}
+
+var numericGoVersion = regexp.MustCompile(`^go[0-9]\.[0-9]+`)
+
+func byCompiler(s string) string {
+	if m := numericGoVersion.FindString(s); m != "" {
+		return m
+	}
+	return "Other"
+}
+
+func versionLess(a, b string) bool {
+	arel, apre := versionParts(a)
+	brel, bpre := versionParts(b)
+
+	minlen := len(arel)
+	if l := len(brel); l < minlen {
+		minlen = l
+	}
+
+	for i := 0; i < minlen; i++ {
+		if arel[i] != brel[i] {
+			return arel[i] < brel[i]
+		}
+	}
+
+	// Longer version is newer, when the preceding parts are equal
+	if len(arel) != len(brel) {
+		return len(arel) < len(brel)
+	}
+
+	if apre != bpre {
+		// "(+dev)" versions are ahead
+		if apre == plusStr {
+			return false
+		}
+		if bpre == plusStr {
+			return true
+		}
+		return apre < bpre
+	}
+
+	// don't actually care how the prerelease stuff compares for our purposes
+	return false
+}
+
+// Split a version as returned from transformVersion into parts.
+// "1.2.3-beta.2" -> []int{1, 2, 3}, "beta.2"}
+func versionParts(v string) ([]int, string) {
+	parts := strings.SplitN(v[1:], " ", 2) // " (+dev)" versions
+	if len(parts) == 1 {
+		parts = strings.SplitN(parts[0], "-", 2) // "-rc.1" type versions
+	}
+	fields := strings.Split(parts[0], ".")
+
+	release := make([]int, len(fields))
+	for i, s := range fields {
+		v, _ := strconv.Atoi(s)
+		release[i] = v
+	}
+
+	var prerelease string
+	if len(parts) > 1 {
+		prerelease = parts[1]
+	}
+
+	return release, prerelease
+}
--- a/cmd/ursrv/compiler_test.go
+++ b/cmd/ursrv/compiler_test.go
@@ -0,0 +1,31 @@
+// Copyright (C) 2018 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import "testing"
+
+func TestCompilerRe(t *testing.T) {
+	tests := [][3]string{
+		{`syncthing v0.11.0 (xgcc (Ubuntu 4.9.3-0ubuntu4) 4.9.3 linux-amd64 default) niklas@Niklas-Netbook 2015-04-26 13:15:08 UTC`, "xgcc (Ubuntu 4.9.3-0ubuntu4) 4.9.3", "niklas@Niklas-Netbook"},
+		{`syncthing v0.12.0-rc5 "Beryllium Bedbug" (go1.4.2 linux-arm android) unknown-user@Felix-T420 2015-10-22 18:32:15 UTC`, "go1.4.2", "unknown-user@Felix-T420"},
+		{`syncthing v0.13.0-beta.0+39-ge267bf3 "Copper Cockroach" (go1.4.2 linux-amd64) portage@slevermann.de 2016-01-20 08:41:52 UTC`, "go1.4.2", "portage@slevermann.de"},
+	}
+
+	for _, tc := range tests {
+		m := compilerRe.FindStringSubmatch(tc[0])
+		if len(m) != 3 {
+			t.Errorf("Regexp didn't match %q", tc[0])
+			continue
+		}
+		if m[1] != tc[1] {
+			t.Errorf("Compiler %q != %q", m[1], tc[1])
+		}
+		if m[2] != tc[2] {
+			t.Errorf("Builder %q != %q", m[2], tc[2])
+		}
+	}
+}
--- a/cmd/ursrv/formatting.go
+++ b/cmd/ursrv/formatting.go
@@ -0,0 +1,131 @@
+// Copyright (C) 2018 The Syncthing Authors.
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+)
+
+type NumberType int
+
+const (
+	NumberMetric NumberType = iota
+	NumberBinary
+	NumberDuration
+)
+
+func number(ntype NumberType, v float64) string {
+	switch ntype {
+	case NumberMetric:
+		return metric(v)
+	case NumberDuration:
+		return duration(v)
+	case NumberBinary:
+		return binary(v)
+	default:
+		return metric(v)
+	}
+}
+
+type suffix struct {
+	Suffix     string
+	Multiplier float64
+}
+
+var metricSuffixes = []suffix{
+	{"G", 1e9},
+	{"M", 1e6},
+	{"k", 1e3},
+}
+
+var binarySuffixes = []suffix{
+	{"Gi", 1 << 30},
+	{"Mi", 1 << 20},
+	{"Ki", 1 << 10},
+}
+
+var durationSuffix = []suffix{
+	{"year", 365 * 24 * 60 * 60},
+	{"month", 30 * 24 * 60 * 60},
+	{"day", 24 * 60 * 60},
+	{"hour", 60 * 60},
+	{"minute", 60},
+	{"second", 1},
+}
+
+func metric(v float64) string {
+	return withSuffix(v, metricSuffixes, false)
+}
+
+func binary(v float64) string {
+	return withSuffix(v, binarySuffixes, false)
+}
+
+func duration(v float64) string {
+	return withSuffix(v, durationSuffix, true)
+}
+
+func withSuffix(v float64, ps []suffix, pluralize bool) string {
+	for _, p := range ps {
+		if v >= p.Multiplier {
+			suffix := p.Suffix
+			if pluralize && v/p.Multiplier != 1.0 {
+				suffix += "s"
+			}
+			// If the number only has decimal zeroes, strip em off.
+			num := strings.TrimRight(strings.TrimRight(fmt.Sprintf("%.1f", v/p.Multiplier), "0"), ".")
+			return fmt.Sprintf("%s %s", num, suffix)
+		}
+	}
+	return strings.TrimRight(strings.TrimRight(fmt.Sprintf("%.1f", v), "0"), ".")
+}
+
+// commatize returns a number with sep as thousands separators. Handles
+// integers and plain floats.
+func commatize(sep, s string) string {
+	// If no dot, don't do anything.
+	if !strings.ContainsRune(s, '.') {
+		return s
+	}
+	var b bytes.Buffer
+	fs := strings.SplitN(s, ".", 2)
+
+	l := len(fs[0])
+	for i := range fs[0] {
+		b.Write([]byte{s[i]})
+		if i < l-1 && (l-i)%3 == 1 {
+			b.WriteString(sep)
+		}
+	}
+
+	if len(fs) > 1 && len(fs[1]) > 0 {
+		b.WriteString(".")
+		b.WriteString(fs[1])
+	}
+
+	return b.String()
+}
+
+func proportion(m map[string]int, count int) float64 {
+	total := 0
+	isMax := true
+	for _, n := range m {
+		total += n
+		if n > count {
+			isMax = false
+		}
+	}
+	pct := (100 * float64(count)) / float64(total)
+	// To avoid rounding errors in the template, surpassing 100% and breaking
+	// the progress bars.
+	if isMax && len(m) > 1 && count != total {
+		pct -= 0.01
+	}
+	return pct
+}
--- a/cmd/ursrv/main.go
+++ b/cmd/ursrv/main.go
--- a/cmd/ursrv/static/assets/img/favicon.png
+++ b/cmd/ursrv/static/assets/img/favicon.png
--- a/cmd/ursrv/static/bootstrap/css/bootstrap-theme.min.css
+++ b/cmd/ursrv/static/bootstrap/css/bootstrap-theme.min.css
--- a/cmd/ursrv/static/bootstrap/css/bootstrap.min.css
+++ b/cmd/ursrv/static/bootstrap/css/bootstrap.min.css
--- a/Show More
+++ b/Show More