nix mlx compilation for better portability

2026-01-18 02:50:24 -05:00 · 2026-01-13 17:13:28 +00:00
47 changed files with 1592 additions and 2542 deletions
--- a/.github/workflows/build-app.yml
+++ b/.github/workflows/build-app.yml
@@ -1,16 +1,5 @@
 name: Build EXO macOS DMG

-# Release workflow:
-# 1. Create a draft GitHub Release with the tag name (e.g. v1.0.0) and write release notes in markdown
-# 2. Push the tag: git tag v1.0.0 && git push origin v1.0.0
-# 3. This workflow builds, signs, and notarizes the DMG
-# 4. Release notes are embedded in appcast.xml for Sparkle (rendered as markdown)
-# 5. DMG and appcast.xml are uploaded to S3
-# 6. The draft GitHub Release is published with the DMG attached
-#
-# For alpha releases (e.g. v1.0.0-alpha.1): draft release and notes are optional.
-# If no draft exists, a release is auto-created with generated notes.
-
 on:
  workflow_dispatch:
  push:
@@ -22,10 +11,8 @@ on:
 jobs:
  build-macos-app:
    runs-on: "macos-26"
-    permissions:
-      contents: write
    env:
-      SPARKLE_VERSION: 2.9.0-beta.1
+      SPARKLE_VERSION: 2.8.1
      SPARKLE_DOWNLOAD_PREFIX: ${{ secrets.SPARKLE_DOWNLOAD_PREFIX }}
      SPARKLE_FEED_URL: ${{ secrets.SPARKLE_FEED_URL }}
      SPARKLE_ED25519_PUBLIC: ${{ secrets.SPARKLE_ED25519_PUBLIC }}
@@ -100,52 +87,6 @@ jobs:
            exit 1
          fi

-      - name: Fetch and validate release notes
-        if: github.ref_type == 'tag'
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
-          # Find draft release by name using gh release list (more reliable with default token)
-          echo "Looking for draft release named '$GITHUB_REF_NAME'..."
-          DRAFT_EXISTS=$(gh release list --json name,isDraft --jq ".[] | select(.isDraft == true) | select(.name == \"$GITHUB_REF_NAME\") | .name" 2>/dev/null || echo "")
-
-          if [[ -z "$DRAFT_EXISTS" ]]; then
-            if [[ "$IS_ALPHA" == "true" ]]; then
-              echo "No draft release found for alpha tag $GITHUB_REF_NAME (optional for alphas)"
-              echo "HAS_RELEASE_NOTES=false" >> $GITHUB_ENV
-              exit 0
-            fi
-            echo "ERROR: No draft release found for tag $GITHUB_REF_NAME"
-            echo "Please create a draft release with release notes before pushing the tag."
-            exit 1
-          fi
-
-          # Fetch full release details via API to get body and ID
-          echo "Found draft release, fetching details..."
-          RELEASE_JSON=$(gh api repos/${{ github.repository }}/releases --jq ".[] | select(.draft == true) | select(.name == \"$GITHUB_REF_NAME\")" 2>/dev/null || echo "")
-
-          # Extract release notes
-          NOTES=$(echo "$RELEASE_JSON" | jq -r '.body // ""')
-          if [[ -z "$NOTES" || "$NOTES" == "null" ]]; then
-            if [[ "$IS_ALPHA" == "true" ]]; then
-              echo "Draft release has no notes (optional for alphas)"
-              echo "HAS_RELEASE_NOTES=false" >> $GITHUB_ENV
-              exit 0
-            fi
-            echo "ERROR: Draft release exists but has no release notes"
-            echo "Please add release notes to the draft release before pushing the tag."
-            exit 1
-          fi
-
-          # Save release ID for later publishing
-          RELEASE_ID=$(echo "$RELEASE_JSON" | jq -r '.id')
-          echo "DRAFT_RELEASE_ID=$RELEASE_ID" >> $GITHUB_ENV
-          echo "HAS_RELEASE_NOTES=true" >> $GITHUB_ENV
-
-          echo "Found draft release (ID: $RELEASE_ID), saving release notes..."
-          echo "$NOTES" > /tmp/release_notes.md
-          echo "RELEASE_NOTES_FILE=/tmp/release_notes.md" >> $GITHUB_ENV
-
      # ============================================================
      # Install dependencies
      # ============================================================
@@ -172,22 +113,11 @@ jobs:
          uv python install
          uv sync --locked

-      - name: Install Nix
-        uses: cachix/install-nix-action@v31
-        with:
-          nix_path: nixpkgs=channel:nixos-unstable
-
-      - name: Configure Cachix
-        uses: cachix/cachix-action@v14
-        with:
-          name: exo
-          authToken: "${{ secrets.CACHIX_AUTH_TOKEN }}"
-
      - name: Build dashboard
        run: |
-          DASHBOARD_OUT=$(nix build .#dashboard --print-build-logs --no-link --print-out-paths)
-          mkdir -p dashboard/build
-          cp -r "$DASHBOARD_OUT"/* dashboard/build/
+          cd dashboard
+          npm ci
+          npm run build

      - name: Install Sparkle CLI
        run: |
@@ -363,28 +293,6 @@ jobs:
            $CHANNEL_FLAG \
            .

-      - name: Inject release notes into appcast
-        if: github.ref_type == 'tag' && env.HAS_RELEASE_NOTES == 'true'
-        env:
-          RELEASE_VERSION: ${{ env.RELEASE_VERSION }}
-        run: |
-          # Inject markdown release notes with sparkle:format="markdown" (Sparkle 2.9+)
-          export NOTES=$(cat "$RELEASE_NOTES_FILE")
-
-          # Insert description after the enclosure tag for this version
-          awk '
-            /<enclosure[^>]*>/ && index($0, ENVIRON["RELEASE_VERSION"]) {
-              print
-              print "            <description sparkle:format=\"markdown\"><![CDATA["
-              print ENVIRON["NOTES"]
-              print "            ]]></description>"
-              next
-            }
-            { print }
-          ' output/appcast.xml > output/appcast.xml.tmp && mv output/appcast.xml.tmp output/appcast.xml
-
-          echo "Injected markdown release notes for version $RELEASE_VERSION"
-
      # ============================================================
      # Upload artifacts
      # ============================================================
@@ -417,26 +325,3 @@ jobs:
            aws s3 cp "$DMG_NAME" "s3://${SPARKLE_S3_BUCKET}/${PREFIX}EXO-latest.dmg"
            aws s3 cp appcast.xml "s3://${SPARKLE_S3_BUCKET}/${PREFIX}appcast.xml" --content-type application/xml --cache-control no-cache
          fi
-
-      - name: Publish GitHub Release
-        if: github.ref_type == 'tag'
-        env:
-          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
-          DMG_PATH="output/EXO-${RELEASE_VERSION}.dmg"
-
-          if [[ "$HAS_RELEASE_NOTES" == "true" ]]; then
-            # Update the draft release with the tag and upload DMG
-            gh api --method PATCH "repos/${{ github.repository }}/releases/$DRAFT_RELEASE_ID" \
-              -f tag_name="$GITHUB_REF_NAME" \
-              -F draft=false
-            gh release upload "$GITHUB_REF_NAME" "$DMG_PATH" --clobber
-            echo "Published release $GITHUB_REF_NAME with DMG attached"
-          else
-            # Alpha without draft release - create one with auto-generated notes
-            gh release create "$GITHUB_REF_NAME" "$DMG_PATH" \
-              --title "$GITHUB_REF_NAME" \
-              --generate-notes \
-              --prerelease
-            echo "Created alpha release $GITHUB_REF_NAME with auto-generated notes"
-          fi
--- a/.github/workflows/pipeline.yml
+++ b/.github/workflows/pipeline.yml
@@ -113,6 +113,28 @@ jobs:
        with:
          lfs: false

+      - name: Select Xcode
+        if: startsWith(matrix.runner, 'macos-')
+        run: |
+          XCODE_BASEDIR="$(printf '%s\n' /Applications/Xcode_*.app | sort -V | tail -n 1)"
+          [[ -z "$XCODE_BASEDIR" ]] && exit 1
+          sudo mv "$XCODE_BASEDIR" /Applications/Xcode.app
+
+          ls -ld "/Applications/Xcode.app"
+          sudo /usr/bin/xcode-select -s "/Applications/Xcode.app"
+          /usr/bin/xcode-select -p || true
+          /usr/bin/xcrun --toolchain default --find xcodebuild || true
+
+      - name: Install Metal toolchain component
+        if: startsWith(matrix.runner, 'macos-')
+        run: |
+          set -e
+          if ! xcrun --find metal >/dev/null 2>&1; then
+            sudo xcodebuild -downloadComponent MetalToolchain
+          fi
+          xcrun --find metal
+          xcrun --find metallib
+
      - uses: cachix/install-nix-action@v31
        with:
          nix_path: nixpkgs=channel:nixos-unstable
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -40,31 +40,6 @@ uv run ruff check
 nix fmt
 ```

-## Pre-Commit Checks (REQUIRED)
-
-**IMPORTANT: Always run these checks before committing code. CI will fail if these don't pass.**
-
-```bash
-# 1. Type checking - MUST pass with 0 errors
-uv run basedpyright
-
-# 2. Linting - MUST pass
-uv run ruff check
-
-# 3. Formatting - MUST be applied
-nix fmt
-
-# 4. Tests - MUST pass
-uv run pytest
-```
-
-Run all checks in sequence:
-```bash
-uv run basedpyright && uv run ruff check && nix fmt && uv run pytest
-```
-
-If `nix fmt` changes any files, stage them before committing. The CI runs `nix flake check` which verifies formatting, linting, and runs Rust tests.
-
 ## Architecture

 ### Node Composition
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4340,6 +4340,25 @@ dependencies = [
 "libc",
 ]

+[[package]]
+name = "system_custodian"
+version = "0.0.1"
+dependencies = [
+ "delegate",
+ "derive_more",
+ "either",
+ "extend",
+ "futures",
+ "futures-timer",
+ "impl-trait-for-tuples",
+ "keccak-const",
+ "log",
+ "thiserror 2.0.17",
+ "tokio",
+ "tracing-subscriber",
+ "util",
+]
+
 [[package]]
 name = "tagptr"
 version = "0.2.0"
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -3,6 +3,7 @@ resolver = "3"
 members = [
    "rust/networking",
    "rust/exo_pyo3_bindings",
+    "rust/system_custodian",
    "rust/util",
 ]

@@ -24,6 +25,7 @@ opt-level = 3
 [workspace.dependencies]
 ## Crate members as common dependencies
 networking = { path = "rust/networking" }
+system_custodian = { path = "rust/system_custodian" }
 util = { path = "rust/util" }

 # Proc-macro authoring tools
--- a/app/EXO/EXO.xcodeproj/project.pbxproj
+++ b/app/EXO/EXO.xcodeproj/project.pbxproj
@@ -585,7 +585,7 @@
 			repositoryURL = "https://github.com/sparkle-project/Sparkle.git";
 			requirement = {
 				kind = upToNextMajorVersion;
-				minimumVersion = 2.9.0-beta.1;
+				minimumVersion = 2.8.1;
 			};
 		};
 /* End XCRemoteSwiftPackageReference section */
--- a/app/EXO/EXO.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved
+++ b/app/EXO/EXO.xcodeproj/project.xcworkspace/xcshareddata/swiftpm/Package.resolved
@@ -6,8 +6,8 @@
      "kind" : "remoteSourceControl",
      "location" : "https://github.com/sparkle-project/Sparkle.git",
      "state" : {
-        "revision" : "e641adb41915a8409895e2e30666aa64e487b637",
-        "version" : "2.9.0-beta.1"
+        "revision" : "5581748cef2bae787496fe6d61139aebe0a451f6",
+        "version" : "2.8.1"
      }
    }
  ],
--- a/app/EXO/EXO/ContentView.swift
+++ b/app/EXO/EXO/ContentView.swift
@@ -56,11 +56,6 @@ struct ContentView: View {
    }

    private var shouldShowLocalNetworkWarning: Bool {
-        // Show warning if local network is not working and EXO is running.
-        // The checker uses a longer timeout on first launch to allow time for
-        // the permission prompt, so this correctly handles both:
-        // 1. User denied permission on first launch
-        // 2. Permission broke after restart (macOS TCC bug)
        if case .notWorking = localNetworkChecker.status {
            return controller.status != .stopped
        }
--- a/app/EXO/EXO/Services/LocalNetworkChecker.swift
+++ b/app/EXO/EXO/Services/LocalNetworkChecker.swift
@@ -5,8 +5,8 @@ import os.log
 /// Checks if the app's local network permission is actually functional.
 ///
 /// macOS local network permission can appear enabled in System Preferences but not
-/// actually work after a restart. This service uses NWConnection to mDNS multicast
-/// to verify actual connectivity.
+/// actually work after a restart. This service detects this by creating a UDP
+/// connection to the mDNS multicast address (224.0.0.251:5353).
@MainActor
 final class LocalNetworkChecker: ObservableObject {
    enum Status: Equatable {
@@ -35,43 +35,30 @@ final class LocalNetworkChecker: ObservableObject {
    }

    private static let logger = Logger(subsystem: "io.exo.EXO", category: "LocalNetworkChecker")
-    private static let hasCompletedInitialCheckKey = "LocalNetworkChecker.hasCompletedInitialCheck"

    @Published private(set) var status: Status = .unknown
+    @Published private(set) var lastConnectionState: String = "none"

    private var connection: NWConnection?
    private var checkTask: Task<Void, Never>?

-    /// Whether we've completed at least one check (stored in UserDefaults)
-    private var hasCompletedInitialCheck: Bool {
-        get { UserDefaults.standard.bool(forKey: Self.hasCompletedInitialCheckKey) }
-        set { UserDefaults.standard.set(newValue, forKey: Self.hasCompletedInitialCheckKey) }
-    }
-
    /// Checks if local network access is working.
    func check() {
        checkTask?.cancel()
        status = .checking
-
-        // Use longer timeout on first launch to allow time for permission prompt
-        let isFirstCheck = !hasCompletedInitialCheck
-        let timeout: UInt64 = isFirstCheck ? 30_000_000_000 : 3_000_000_000
+        lastConnectionState = "connecting"

        checkTask = Task { [weak self] in
            guard let self else { return }
-
-            Self.logger.info("Checking local network connectivity (first check: \(isFirstCheck))")
-            let result = await self.checkConnectivity(timeout: timeout)
+            let result = await self.performCheck()
            self.status = result
-            self.hasCompletedInitialCheck = true
-
            Self.logger.info("Local network check complete: \(result.displayText)")
        }
    }

-    /// Checks connectivity using NWConnection to mDNS multicast.
-    /// The connection attempt triggers the permission prompt if not yet shown.
-    private func checkConnectivity(timeout: UInt64) async -> Status {
+    private func performCheck() async -> Status {
+        Self.logger.info("Checking local network access via UDP multicast")
+
        connection?.cancel()
        connection = nil

@@ -97,7 +84,22 @@ final class LocalNetworkChecker: ObservableObject {
                continuation.resume(returning: status)
            }

-            conn.stateUpdateHandler = { state in
+            conn.stateUpdateHandler = { [weak self] state in
+                let stateStr: String
+                switch state {
+                case .setup: stateStr = "setup"
+                case .preparing: stateStr = "preparing"
+                case .ready: stateStr = "ready"
+                case .waiting(let e): stateStr = "waiting(\(e))"
+                case .failed(let e): stateStr = "failed(\(e))"
+                case .cancelled: stateStr = "cancelled"
+                @unknown default: stateStr = "unknown"
+                }
+
+                Task { @MainActor in
+                    self?.lastConnectionState = stateStr
+                }
+
                switch state {
                case .ready:
                    resumeOnce(.working)
@@ -106,7 +108,6 @@ final class LocalNetworkChecker: ObservableObject {
                    if errorStr.contains("54") || errorStr.contains("ECONNRESET") {
                        resumeOnce(.notWorking(reason: "Connection blocked"))
                    }
-                // Otherwise keep waiting - might be showing permission prompt
                case .failed(let error):
                    let errorStr = "\(error)"
                    if errorStr.contains("65") || errorStr.contains("EHOSTUNREACH")
@@ -126,7 +127,7 @@ final class LocalNetworkChecker: ObservableObject {
            conn.start(queue: .main)

            Task {
-                try? await Task.sleep(nanoseconds: timeout)
+                try? await Task.sleep(nanoseconds: 3_000_000_000)
                let state = conn.state
                switch state {
                case .ready:
--- a/bench/exo_bench.py
+++ b/bench/exo_bench.py
@@ -3,7 +3,6 @@
 from __future__ import annotations

 import argparse
-import contextlib
 import http.client
 import json
 import os
@@ -27,7 +26,7 @@ class ExoHttpError(RuntimeError):


 class ExoClient:
-    def __init__(self, host: str, port: int, timeout_s: float = 600.0):
+    def __init__(self, host: str, port: int, timeout_s: float = 2400.0):
        self.host = host
        self.port = port
        self.timeout_s = timeout_s
@@ -105,46 +104,22 @@ def runner_ready(runner: dict[str, Any]) -> bool:
    return "RunnerReady" in runner


-def runner_failed(runner: dict[str, Any]) -> bool:
-    return "RunnerFailed" in runner
-
-
-def get_runner_failed_message(runner: dict[str, Any]) -> str | None:
-    if "RunnerFailed" in runner:
-        return runner["RunnerFailed"].get("errorMessage")
-    return None
-
-
 def wait_for_instance_ready(
    client: ExoClient, instance_id: str, timeout: float = 24000.0
 ) -> None:
    start_time = time.time()
-    instance_existed = False
    while time.time() - start_time < timeout:
        state = client.request_json("GET", "/state")
        instances = state.get("instances", {})

        if instance_id not in instances:
-            if instance_existed:
-                # Instance was deleted after being created - likely due to runner failure
-                raise RuntimeError(
-                    f"Instance {instance_id} was deleted (runner may have failed)"
-                )
            time.sleep(0.1)
            continue

-        instance_existed = True
        instance = instances[instance_id]
        runner_ids = runner_ids_from_instance(instance)
        runners = state.get("runners", {})

-        # Check for failed runners first
-        for rid in runner_ids:
-            runner = runners.get(rid, {})
-            if runner_failed(runner):
-                error_msg = get_runner_failed_message(runner) or "Unknown error"
-                raise RuntimeError(f"Runner {rid} failed: {error_msg}")
-
        if all(runner_ready(runners.get(rid, {})) for rid in runner_ids):
            return

@@ -266,9 +241,6 @@ class PromptSizer:
            ids = tokenizer.apply_chat_template(
                messages, tokenize=True, add_generation_prompt=True
            )
-            # Fix for transformers 5.x
-            if hasattr(ids, "input_ids"):
-                ids = ids.input_ids
            return int(len(ids))

        return count_fn
@@ -324,12 +296,6 @@ def main() -> int:
        default=4,
        help="Only consider placements using <= this many nodes.",
    )
-    ap.add_argument(
-        "--min-nodes",
-        type=int,
-        default=1,
-        help="Only consider placements using >= this many nodes.",
-    )
    ap.add_argument(
        "--instance-meta", choices=["ring", "jaccl", "both"], default="both"
    )
@@ -351,7 +317,7 @@ def main() -> int:
        help="Warmup runs per placement (uses first pp/tg).",
    )
    ap.add_argument(
-        "--timeout", type=float, default=600.0, help="HTTP timeout (seconds)."
+        "--timeout", type=float, default=2400.0, help="HTTP timeout (seconds)."
    )
    ap.add_argument(
        "--json-out",
@@ -430,7 +396,7 @@ def main() -> int:
        ):
            continue

-        if args.min_nodes <= n <= args.max_nodes:
+        if 0 < n <= args.max_nodes:
            selected.append(p)

    if not selected:
@@ -472,13 +438,7 @@ def main() -> int:
        )

        client.request_json("POST", "/instance", body={"instance": instance})
-        try:
-            wait_for_instance_ready(client, instance_id)
-        except (RuntimeError, TimeoutError) as e:
-            logger.error(f"Failed to initialize placement: {e}")
-            with contextlib.suppress(ExoHttpError):
-                client.request_json("DELETE", f"/instance/{instance_id}")
-            continue
+        wait_for_instance_ready(client, instance_id)

        time.sleep(1)

--- a/dashboard/dashboard.nix
+++ b/dashboard/dashboard.nix
@@ -1,60 +0,0 @@
-{ lib
-, config
-, dream2nix
-, ...
-}:
-let
-  # Read and parse the lock file
-  rawLockFile = builtins.fromJSON (builtins.readFile "${config.deps.dashboardSrc}/package-lock.json");
-
-  # For packages with bundleDependencies, filter out deps that are bundled
-  # (bundled deps are inside the tarball, not separate lockfile entries)
-  fixedPackages = lib.mapAttrs
-    (path: entry:
-      if entry ? bundleDependencies && entry.bundleDependencies != [ ]
-      then entry // {
-        dependencies = lib.filterAttrs
-          (name: _: !(lib.elem name entry.bundleDependencies))
-          (entry.dependencies or { });
-      }
-      else entry
-    )
-    (rawLockFile.packages or { });
-
-  fixedLockFile = rawLockFile // { packages = fixedPackages; };
-in
-{
-  imports = [
-    dream2nix.modules.dream2nix.nodejs-package-lock-v3
-    dream2nix.modules.dream2nix.nodejs-granular-v3
-  ];
-
-  name = "exo-dashboard";
-  version = "1.0.0";
-
-  mkDerivation = {
-    src = config.deps.dashboardSrc;
-
-    buildPhase = ''
-      runHook preBuild
-      npm run build
-      runHook postBuild
-    '';
-
-    installPhase = ''
-      runHook preInstall
-      cp -r build $out/build
-      runHook postInstall
-    '';
-  };
-
-  deps = { nixpkgs, ... }: {
-    inherit (nixpkgs) stdenv;
-    dashboardSrc = null; # Injected by parts.nix
-  };
-
-  nodejs-package-lock-v3 = {
-    # Don't use packageLockFile - provide the fixed lock content directly
-    packageLock = fixedLockFile;
-  };
-}
--- a/dashboard/package-lock.json
+++ b/dashboard/package-lock.json
@@ -863,7 +863,6 @@
 			"integrity": "sha512-oH8tXw7EZnie8FdOWYrF7Yn4IKrqTFHhXvl8YxXxbKwTMcD/5NNCryUSEXRk2ZR4ojnub0P8rNrsVGHXWqIDtA==",
 			"dev": true,
 			"license": "MIT",
-			"peer": true,
 			"dependencies": {
 				"@standard-schema/spec": "^1.0.0",
 				"@sveltejs/acorn-typescript": "^1.0.5",
@@ -903,7 +902,6 @@
 			"integrity": "sha512-Y1Cs7hhTc+a5E9Va/xwKlAJoariQyHY+5zBgCZg4PFWNYQ1nMN9sjK1zhw1gK69DuqVP++sht/1GZg1aRwmAXQ==",
 			"dev": true,
 			"license": "MIT",
-			"peer": true,
 			"dependencies": {
 				"@sveltejs/vite-plugin-svelte-inspector": "^4.0.1",
 				"debug": "^4.4.1",
@@ -1520,7 +1518,6 @@
 			"integrity": "sha512-LCCV0HdSZZZb34qifBsyWlUmok6W7ouER+oQIGBScS8EsZsQbrtFTUrDX4hOl+CS6p7cnNC4td+qrSVGSCTUfQ==",
 			"dev": true,
 			"license": "MIT",
-			"peer": true,
 			"dependencies": {
 				"undici-types": "~6.21.0"
 			}
@@ -1530,7 +1527,6 @@
 			"resolved": "https://registry.npmjs.org/acorn/-/acorn-8.15.0.tgz",
 			"integrity": "sha512-NZyJarBfL7nWwIq+FDL6Zp/yHEhePMNnnJ0y3qfieCrmNvYct8uvtiV41UvlSe6apAfk0fY1FbWx+NwfmpvtTg==",
 			"license": "MIT",
-			"peer": true,
 			"bin": {
 				"acorn": "bin/acorn"
 			},
@@ -1943,7 +1939,6 @@
 			"integrity": "sha512-fmTRWbNMmsmWq6xJV8D19U/gw/bwrHfNXxrIN+HfZgnzqTHp9jOmKMhsTUjXOJnZOdZY9Q28y4yebKzqDKlxlQ==",
 			"dev": true,
 			"license": "ISC",
-			"peer": true,
 			"engines": {
 				"node": ">=12"
 			}
@@ -2651,7 +2646,6 @@
 			"integrity": "sha512-5gTmgEY/sqK6gFXLIsQNH19lWb4ebPDLA4SdLP7dsWkIXHWlG66oPuVvXSGFPppYZz8ZDZq0dYYrbHfBCVUb1Q==",
 			"dev": true,
 			"license": "MIT",
-			"peer": true,
 			"engines": {
 				"node": ">=12"
 			},
@@ -2839,7 +2833,6 @@
 			"resolved": "https://registry.npmjs.org/svelte/-/svelte-5.45.3.tgz",
 			"integrity": "sha512-ngKXNhNvwPzF43QqEhDOue7TQTrG09em1sd4HBxVF0Wr2gopAmdEWan+rgbdgK4fhBtSOTJO8bYU4chUG7VXZQ==",
 			"license": "MIT",
-			"peer": true,
 			"dependencies": {
 				"@jridgewell/remapping": "^2.3.4",
 				"@jridgewell/sourcemap-codec": "^1.5.0",
@@ -2984,7 +2977,6 @@
 			"integrity": "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw==",
 			"dev": true,
 			"license": "Apache-2.0",
-			"peer": true,
 			"bin": {
 				"tsc": "bin/tsc",
 				"tsserver": "bin/tsserver"
@@ -3006,7 +2998,6 @@
 			"integrity": "sha512-+Oxm7q9hDoLMyJOYfUYBuHQo+dkAloi33apOPP56pzj+vsdJDzr+j1NISE5pyaAuKL4A3UD34qd0lx5+kfKp2g==",
 			"dev": true,
 			"license": "MIT",
-			"peer": true,
 			"dependencies": {
 				"esbuild": "^0.25.0",
 				"fdir": "^6.4.4",
--- a/dashboard/parts.nix
+++ b/dashboard/parts.nix
@@ -1,44 +0,0 @@
-{ inputs, ... }:
-{
-  perSystem =
-    { pkgs, lib, ... }:
-    let
-      # Filter source to only include dashboard directory
-      src = lib.cleanSourceWith {
-        src = inputs.self;
-        filter =
-          path: type:
-          let
-            baseName = builtins.baseNameOf path;
-            inDashboardDir =
-              (lib.hasInfix "/dashboard/" path)
-              || (lib.hasSuffix "/dashboard" (builtins.dirOf path))
-              || (baseName == "dashboard" && type == "directory");
-          in
-          inDashboardDir;
-      };
-
-      # Build the dashboard with dream2nix (includes node_modules in output)
-      dashboardFull = inputs.dream2nix.lib.evalModules {
-        packageSets.nixpkgs = pkgs;
-        modules = [
-          ./dashboard.nix
-          {
-            paths.projectRoot = inputs.self;
-            paths.projectRootFile = "flake.nix";
-            paths.package = inputs.self + "/dashboard";
-          }
-          # Inject the filtered source
-          {
-            deps.dashboardSrc = lib.mkForce "${src}/dashboard";
-          }
-        ];
-      };
-    in
-    {
-      # Extract just the static site from the full build
-      packages.dashboard = pkgs.runCommand "exo-dashboard" { } ''
-        cp -r ${dashboardFull}/build $out
-      '';
-    };
-}
--- a/dashboard/src/lib/components/ChatForm.svelte
+++ b/dashboard/src/lib/components/ChatForm.svelte
@@ -60,39 +60,12 @@
 		return models;
 	});

-	// Track previous model IDs to detect newly added models (plain variable to avoid reactive loop)
-	let previousModelIds: Set<string> = new Set();
-
-	// Auto-select the first available model if none is selected, if current selection is stale, or if a new model is added
+	// Auto-select the first available model if none is selected
 	$effect(() => {
 		const models = availableModels();
-		const currentModelIds = new Set(models.map(m => m.id));
-
-		if (models.length > 0) {
-			// Find newly added models (in current but not in previous)
-			const newModels = models.filter(m => !previousModelIds.has(m.id));
-
-			// If no model selected, select the first available
-			if (!currentModel) {
-				setSelectedChatModel(models[0].id);
-			}
-			// If current model is stale (no longer has a running instance), reset to first available
-			else if (!models.some(m => m.id === currentModel)) {
-				setSelectedChatModel(models[0].id);
-			}
-			// If a new model was just added, select it
-			else if (newModels.length > 0 && previousModelIds.size > 0) {
-				setSelectedChatModel(newModels[0].id);
-			}
-		} else {
-			// No instances running - clear the selected model
-			if (currentModel) {
-				setSelectedChatModel('');
-			}
+		if (models.length > 0 && !currentModel) {
+			setSelectedChatModel(models[0].id);
 		}
-
-		// Update previous model IDs for next comparison
-		previousModelIds = currentModelIds;
 	});

 	function getInstanceModelId(instanceWrapped: unknown): string {
--- a/dashboard/src/lib/stores/app.svelte.ts
+++ b/dashboard/src/lib/stores/app.svelte.ts
@@ -69,8 +69,6 @@ export interface Instance {
 		runnerToShard?: Record<string, unknown>;
 		nodeToRunner?: Record<string, string>;
 	};
-	draftModel?: string;
-	numDraftTokens?: number;
 }

 interface RawNodeProfile {
--- a/dashboard/src/routes/+page.svelte
+++ b/dashboard/src/routes/+page.svelte
@@ -47,7 +47,7 @@ const sidebarVisible = $derived(chatSidebarVisible());
 	let mounted = $state(false);

 	// Instance launch state
-	let models = $state<Array<{id: string, hugging_face_id?: string, name?: string, storage_size_megabytes?: number}>>([]);
+	let models = $state<Array<{id: string, name?: string, storage_size_megabytes?: number}>>([]);
 	let selectedSharding = $state<'Pipeline' | 'Tensor'>('Pipeline');
 	type InstanceMeta = 'MlxRing' | 'MlxIbv' | 'MlxJaccl';
 	
@@ -58,8 +58,6 @@ const sidebarVisible = $derived(chatSidebarVisible());
 		sharding: 'Pipeline' | 'Tensor';
 		instanceType: InstanceMeta;
 		minNodes: number;
-		draftModel: string | null;
-		numDraftTokens: number;
 	}
 	
 	function saveLaunchDefaults(): void {
@@ -68,8 +66,6 @@ const sidebarVisible = $derived(chatSidebarVisible());
 			sharding: selectedSharding,
 			instanceType: selectedInstanceType,
 			minNodes: selectedMinNodes,
-			draftModel: selectedDraftModel,
-			numDraftTokens: selectedNumDraftTokens,
 		};
 		try {
 			localStorage.setItem(LAUNCH_DEFAULTS_KEY, JSON.stringify(defaults));
@@ -92,36 +88,24 @@ const sidebarVisible = $derived(chatSidebarVisible());
 	function applyLaunchDefaults(availableModels: Array<{id: string}>, maxNodes: number): void {
 		const defaults = loadLaunchDefaults();
 		if (!defaults) return;
-
+		
 		// Apply sharding and instance type unconditionally
 		selectedSharding = defaults.sharding;
 		selectedInstanceType = defaults.instanceType;
-
+		
 		// Apply minNodes if valid (between 1 and maxNodes)
 		if (defaults.minNodes && defaults.minNodes >= 1 && defaults.minNodes <= maxNodes) {
 			selectedMinNodes = defaults.minNodes;
 		}
-
+		
 		// Only apply model if it exists in the available models
 		if (defaults.modelId && availableModels.some(m => m.id === defaults.modelId)) {
 			selectPreviewModel(defaults.modelId);
 		}
-
-		// Apply draft model if it exists in the available models (check against hugging_face_id)
-		if (defaults.draftModel && availableModels.some(m => (m as {hugging_face_id?: string}).hugging_face_id === defaults.draftModel)) {
-			selectedDraftModel = defaults.draftModel;
-		}
-
-		// Apply num draft tokens if valid
-		if (defaults.numDraftTokens && defaults.numDraftTokens >= 1 && defaults.numDraftTokens <= 10) {
-			selectedNumDraftTokens = defaults.numDraftTokens;
-		}
 	}
 	
 	let selectedInstanceType = $state<InstanceMeta>('MlxRing');
 	let selectedMinNodes = $state<number>(1);
-	let selectedDraftModel = $state<string | null>(null);
-	let selectedNumDraftTokens = $state<number>(4);
 	let minNodesInitialized = $state(false);
 	let launchingModelId = $state<string | null>(null);
 let instanceDownloadExpandedNodes = $state<Set<string>>(new Set());
@@ -129,8 +113,6 @@ let instanceDownloadExpandedNodes = $state<Set<string>>(new Set());
 	// Custom dropdown state
 	let isModelDropdownOpen = $state(false);
 	let modelDropdownSearch = $state('');
-	let isDraftModelDropdownOpen = $state(false);
-	let draftModelDropdownSearch = $state('');
 	
 	// Slider dragging state
 	let isDraggingSlider = $state(false);
@@ -380,39 +362,49 @@ function toggleInstanceDownloadDetails(nodeId: string): void {

 	async function launchInstance(modelId: string, specificPreview?: PlacementPreview | null) {
 		if (!modelId || launchingModelId) return;
-
+		
 		launchingModelId = modelId;
-
+		
 		try {
 			// Use the specific preview if provided, otherwise fall back to filtered preview
 			const preview = specificPreview ?? filteredPreview();
-
-			let response: Response;
-
-			// Use /place_instance endpoint - it handles placement and creation in one step
-			// This also supports draft_model for speculative decoding
-			const placePayload = {
-				model_id: modelId,
-				sharding: preview?.sharding ?? selectedSharding,
-				instance_meta: preview?.instance_meta ?? selectedInstanceType,
-				min_nodes: selectedMinNodes,
-				draft_model: selectedDraftModel,
-				num_draft_tokens: selectedDraftModel ? selectedNumDraftTokens : 4,
-			};
-
-			response = await fetch('/place_instance', {
+			
+			let instanceData: unknown;
+			
+			if (preview?.instance) {
+				// Use the instance from the preview
+				instanceData = preview.instance;
+			} else {
+				// Fallback: GET placement from API
+				const placementResponse = await fetch(
+					`/instance/placement?model_id=${encodeURIComponent(modelId)}&sharding=${selectedSharding}&instance_meta=${selectedInstanceType}&min_nodes=${selectedMinNodes}`
+				);
+				
+				if (!placementResponse.ok) {
+					const errorText = await placementResponse.text();
+					console.error('Failed to get placement:', errorText);
+					return;
+				}
+				
+				instanceData = await placementResponse.json();
+			}
+			
+			// POST the instance to create it
+			const response = await fetch('/instance', {
 				method: 'POST',
 				headers: { 'Content-Type': 'application/json' },
-				body: JSON.stringify(placePayload)
+				body: JSON.stringify({ instance: instanceData })
 			});
-
+			
 			if (!response.ok) {
 				const errorText = await response.text();
 				console.error('Failed to launch instance:', errorText);
 			} else {
-				// Always auto-select the newly launched model so the user chats to what they just launched
-				setSelectedChatModel(modelId);
-
+				// Auto-select the launched model only if no model is currently selected
+				if (!selectedChatModel()) {
+					setSelectedChatModel(modelId);
+				}
+				
 				// Scroll to the bottom of instances container to show the new instance
 				// Use multiple attempts to ensure DOM has updated with the new instance
 				const scrollToBottom = () => {
@@ -771,10 +763,6 @@ function toggleInstanceDownloadDetails(nodeId: string): void {
 	async function deleteInstance(instanceId: string) {
 		if (!confirm(`Delete instance ${instanceId.slice(0, 8)}...?`)) return;
 		
-		// Get the model ID of the instance being deleted before we delete it
-		const deletedInstanceModelId = getInstanceModelId(instanceData[instanceId]);
-		const wasSelected = selectedChatModel() === deletedInstanceModelId;
-		
 		try {
 			const response = await fetch(`/instance/${instanceId}`, {
 				method: 'DELETE',
@@ -783,24 +771,6 @@ function toggleInstanceDownloadDetails(nodeId: string): void {
 			
 			if (!response.ok) {
 				console.error('Failed to delete instance:', response.status);
-			} else if (wasSelected) {
-				// If we deleted the currently selected model, switch to another available model
-				// Find another instance that isn't the one we just deleted
-				const remainingInstances = Object.entries(instanceData).filter(([id]) => id !== instanceId);
-				if (remainingInstances.length > 0) {
-					// Select the last instance (most recently added, since objects preserve insertion order)
-					const [, lastInstance] = remainingInstances[remainingInstances.length - 1];
-					const newModelId = getInstanceModelId(lastInstance);
-					if (newModelId && newModelId !== 'Unknown' && newModelId !== 'Unknown Model') {
-						setSelectedChatModel(newModelId);
-					} else {
-						// Clear selection if no valid model found
-						setSelectedChatModel('');
-					}
-				} else {
-					// No more instances, clear the selection
-					setSelectedChatModel('');
-				}
 			}
 		} catch (error) {
 			console.error('Error deleting instance:', error);
@@ -826,34 +796,30 @@ function toggleInstanceDownloadDetails(nodeId: string): void {
 	}

 	// Get instance details: type (MLX Ring/IBV), sharding (Pipeline/Tensor), and node names
-	function getInstanceInfo(instanceWrapped: unknown): {
-		instanceType: string;
-		sharding: string;
+	function getInstanceInfo(instanceWrapped: unknown): { 
+		instanceType: string; 
+		sharding: string; 
 		nodeNames: string[];
 		nodeIds: string[];
 		nodeCount: number;
-		draftModel: string | null;
-		numDraftTokens: number | null;
 	} {
 		const [instanceTag, instance] = getTagged(instanceWrapped);
 		if (!instance || typeof instance !== 'object') {
-			return { instanceType: 'Unknown', sharding: 'Unknown', nodeNames: [], nodeIds: [], nodeCount: 0, draftModel: null, numDraftTokens: null };
+			return { instanceType: 'Unknown', sharding: 'Unknown', nodeNames: [], nodeIds: [], nodeCount: 0 };
 		}
-
+		
 		// Instance type from tag
 		let instanceType = 'Unknown';
 		if (instanceTag === 'MlxRingInstance') instanceType = 'MLX Ring';
 		else if (instanceTag === 'MlxIbvInstance' || instanceTag === 'MlxJacclInstance') instanceType = 'MLX RDMA';
-
-		const inst = instance as {
-			shardAssignments?: {
-				nodeToRunner?: Record<string, string>;
+		
+		const inst = instance as { 
+			shardAssignments?: { 
+				nodeToRunner?: Record<string, string>; 
 				runnerToShard?: Record<string, unknown>;
-			};
-			draftModel?: string;
-			numDraftTokens?: number;
+			} 
 		};
-
+		
 		// Sharding strategy from first shard
 		let sharding = 'Unknown';
 		const runnerToShard = inst.shardAssignments?.runnerToShard || {};
@@ -864,7 +830,7 @@ function toggleInstanceDownloadDetails(nodeId: string): void {
 			else if (shardTag === 'TensorShardMetadata') sharding = 'Tensor';
 			else if (shardTag === 'PrefillDecodeShardMetadata') sharding = 'Prefill/Decode';
 		}
-
+		
 		// Node names from topology
 		const nodeToRunner = inst.shardAssignments?.nodeToRunner || {};
 		const nodeIds = Object.keys(nodeToRunner);
@@ -872,12 +838,8 @@ function toggleInstanceDownloadDetails(nodeId: string): void {
 			const node = data?.nodes?.[nodeId];
 			return node?.friendly_name || nodeId.slice(0, 8);
 		});
-
-		// Draft model for speculative decoding
-		const draftModel = inst.draftModel ?? null;
-		const numDraftTokens = inst.numDraftTokens ?? null;
-
-		return { instanceType, sharding, nodeNames, nodeIds, nodeCount: nodeIds.length, draftModel, numDraftTokens };
+		
+		return { instanceType, sharding, nodeNames, nodeIds, nodeCount: nodeIds.length };
 	}

 	function formatLastUpdate(): string {
@@ -1363,9 +1325,6 @@ function toggleInstanceDownloadDetails(nodeId: string): void {
 											<div class="pl-2">
 												<div class="text-exo-yellow text-xs font-mono tracking-wide truncate">{getInstanceModelId(instance)}</div>
 												<div class="text-white/60 text-xs font-mono">Strategy: <span class="text-white/80">{instanceInfo.sharding} ({instanceInfo.instanceType})</span></div>
-												{#if instanceInfo.draftModel}
-													<div class="text-white/60 text-xs font-mono">Draft: <span class="text-cyan-400">{instanceInfo.draftModel.split('/').pop()}</span>{#if instanceInfo.numDraftTokens}<span class="text-white/40"> ({instanceInfo.numDraftTokens}t)</span>{/if}</div>
-												{/if}
 												{#if instanceModelId && instanceModelId !== 'Unknown' && instanceModelId !== 'Unknown Model'}
 													<a
 														class="inline-flex items-center gap-1 text-[11px] text-white/60 hover:text-exo-yellow transition-colors mt-1"
@@ -1699,80 +1658,8 @@ function toggleInstanceDownloadDetails(nodeId: string): void {
 									{/each}
 								</div>
 							</div>
-
-							<!-- Draft Model (Speculative Decoding) -->
-							<div>
-								<div class="text-xs text-white/70 font-mono mb-2">Draft Model (Speculative):</div>
-								<div class="relative">
-									<button
-										onclick={() => { isDraftModelDropdownOpen = !isDraftModelDropdownOpen; draftModelDropdownSearch = ''; }}
-										class="w-full px-3 py-2 text-left text-sm font-mono border rounded transition-all duration-200 cursor-pointer flex items-center justify-between gap-2 {selectedDraftModel ? 'bg-transparent text-exo-yellow border-exo-yellow' : 'bg-transparent text-white/50 border-exo-medium-gray/50 hover:border-exo-yellow/50'}"
-									>
-										<span class="truncate">{selectedDraftModel ? selectedDraftModel.split('/').pop() : 'None'}</span>
-										<svg class="w-4 h-4 flex-shrink-0 transition-transform {isDraftModelDropdownOpen ? 'rotate-180' : ''}" fill="none" stroke="currentColor" viewBox="0 0 24 24">
-											<path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M19 9l-7 7-7-7" />
-										</svg>
-									</button>
-									{#if isDraftModelDropdownOpen}
-										<!-- svelte-ignore a11y_no_static_element_interactions -->
-										<div
-											class="fixed inset-0 z-40"
-											onclick={() => isDraftModelDropdownOpen = false}
-											onkeydown={(e) => e.key === 'Escape' && (isDraftModelDropdownOpen = false)}
-										></div>
-										<div class="absolute top-full left-0 right-0 mt-1 bg-exo-dark-gray border border-exo-medium-gray/50 rounded shadow-lg z-50 max-h-48 overflow-hidden flex flex-col">
-											<div class="p-2 border-b border-exo-medium-gray/30">
-												<input
-													type="text"
-													bind:value={draftModelDropdownSearch}
-													placeholder="Search models..."
-													class="w-full px-2 py-1.5 text-sm font-mono bg-transparent border border-exo-medium-gray/50 rounded text-white/90 placeholder:text-white/30 focus:outline-none focus:border-exo-yellow/50"
-												/>
-											</div>
-											<div class="overflow-y-auto max-h-36">
-												<!-- None option -->
-												<button
-													onclick={() => { selectedDraftModel = null; isDraftModelDropdownOpen = false; saveLaunchDefaults(); }}
-													class="w-full px-3 py-2 text-left text-sm font-mono tracking-wide transition-colors duration-100 flex items-center gap-2 {selectedDraftModel === null ? 'bg-transparent text-exo-yellow cursor-pointer' : 'text-white/80 hover:text-exo-yellow cursor-pointer'}"
-												>
-													<span>None</span>
-												</button>
-												{#each models.filter(m => (m.name ?? m.id).toLowerCase().includes(draftModelDropdownSearch.toLowerCase()) && m.id !== selectedModelId) as model}
-													{@const sizeGB = (model.storage_size_megabytes ?? 0) / 1024}
-													{@const modelHfId = model.hugging_face_id ?? model.id}
-													<button
-														onclick={() => { selectedDraftModel = modelHfId; isDraftModelDropdownOpen = false; saveLaunchDefaults(); }}
-														class="w-full px-3 py-2 text-left text-sm font-mono tracking-wide transition-colors duration-100 flex items-center justify-between gap-2 {selectedDraftModel === modelHfId ? 'bg-transparent text-exo-yellow cursor-pointer' : 'text-white/80 hover:text-exo-yellow cursor-pointer'}"
-													>
-														<span class="truncate">{model.name || model.id}</span>
-														<span class="flex-shrink-0 text-xs text-white/50">
-															{sizeGB >= 1 ? sizeGB.toFixed(0) : sizeGB.toFixed(1)}GB
-														</span>
-													</button>
-												{:else}
-													<div class="px-3 py-2 text-xs text-white/50 font-mono">No models found</div>
-												{/each}
-											</div>
-										</div>
-									{/if}
-								</div>
-							</div>
-							<!-- Draft Tokens (only show when draft model selected) -->
-							{#if selectedDraftModel}
-								<div class="flex items-center gap-2 mt-2">
-									<span class="text-xs text-white/50 font-mono">Tokens:</span>
-									<div class="flex items-center gap-1">
-										{#each [2, 3, 4, 5, 6] as n}
-											<button
-												onclick={() => { selectedNumDraftTokens = n; saveLaunchDefaults(); }}
-												class="w-6 h-6 text-xs font-mono rounded transition-all {selectedNumDraftTokens === n ? 'bg-exo-yellow/20 text-exo-yellow border border-exo-yellow/50' : 'text-white/50 hover:text-white/80 border border-transparent'}"
-											>{n}</button>
-										{/each}
-									</div>
-								</div>
-							{/if}
 						</div>
-
+						
 						<!-- Selected Model Preview -->
 						<div class="space-y-3">
 							{#if models.length === 0}
--- a/flake.lock
+++ b/flake.lock
@@ -1,42 +1,5 @@
 {
  "nodes": {
-    "crane": {
-      "locked": {
-        "lastModified": 1767744144,
-        "narHash": "sha256-9/9ntI0D+HbN4G0TrK3KmHbTvwgswz7p8IEJsWyef8Q=",
-        "owner": "ipetkov",
-        "repo": "crane",
-        "rev": "2fb033290bf6b23f226d4c8b32f7f7a16b043d7e",
-        "type": "github"
-      },
-      "original": {
-        "owner": "ipetkov",
-        "repo": "crane",
-        "type": "github"
-      }
-    },
-    "dream2nix": {
-      "inputs": {
-        "nixpkgs": [
-          "nixpkgs"
-        ],
-        "purescript-overlay": "purescript-overlay",
-        "pyproject-nix": "pyproject-nix"
-      },
-      "locked": {
-        "lastModified": 1765953015,
-        "narHash": "sha256-5FBZbbWR1Csp3Y2icfRkxMJw/a/5FGg8hCXej2//bbI=",
-        "owner": "nix-community",
-        "repo": "dream2nix",
-        "rev": "69eb01fa0995e1e90add49d8ca5bcba213b0416f",
-        "type": "github"
-      },
-      "original": {
-        "owner": "nix-community",
-        "repo": "dream2nix",
-        "type": "github"
-      }
-    },
    "fenix": {
      "inputs": {
        "nixpkgs": [
@@ -45,11 +8,11 @@
        "rust-analyzer-src": "rust-analyzer-src"
      },
      "locked": {
-        "lastModified": 1768287139,
-        "narHash": "sha256-nsXFt0OzUi6K7dUzzJD5/v9e0Ic+fvclfIW936/43ZM=",
+        "lastModified": 1761893049,
+        "narHash": "sha256-1TtFDPhC+ZsrOOtBnry1EZC+WipTTvsOVjIEVugqji8=",
        "owner": "nix-community",
        "repo": "fenix",
-        "rev": "a4a3aa956931f90f35453cb519e4545e9ad7f773",
+        "rev": "c2ac9a5c0d6d16630c3b225b874bd14528d1abe6",
        "type": "github"
      },
      "original": {
@@ -58,22 +21,6 @@
        "type": "github"
      }
    },
-    "flake-compat": {
-      "flake": false,
-      "locked": {
-        "lastModified": 1696426674,
-        "narHash": "sha256-kvjfFW7WAETZlt09AgDn1MrtKzP7t90Vf7vypd3OL1U=",
-        "owner": "edolstra",
-        "repo": "flake-compat",
-        "rev": "0f9255e01c2351cc7d116c072cb317785dd33b33",
-        "type": "github"
-      },
-      "original": {
-        "owner": "edolstra",
-        "repo": "flake-compat",
-        "type": "github"
-      }
-    },
    "flake-parts": {
      "inputs": {
        "nixpkgs-lib": [
@@ -95,22 +42,6 @@
      }
    },
    "nixpkgs": {
-      "locked": {
-        "lastModified": 1768127708,
-        "narHash": "sha256-1Sm77VfZh3mU0F5OqKABNLWxOuDeHIlcFjsXeeiPazs=",
-        "owner": "NixOS",
-        "repo": "nixpkgs",
-        "rev": "ffbc9f8cbaacfb331b6017d5a5abb21a492c9a38",
-        "type": "github"
-      },
-      "original": {
-        "owner": "NixOS",
-        "ref": "nixos-unstable",
-        "repo": "nixpkgs",
-        "type": "github"
-      }
-    },
-    "nixpkgs-swift": {
      "locked": {
        "lastModified": 1761672384,
        "narHash": "sha256-o9KF3DJL7g7iYMZq9SWgfS1BFlNbsm6xplRjVlOCkXI=",
@@ -121,74 +52,27 @@
      },
      "original": {
        "owner": "NixOS",
+        "ref": "nixos-unstable",
        "repo": "nixpkgs",
-        "rev": "08dacfca559e1d7da38f3cf05f1f45ee9bfd213c",
-        "type": "github"
-      }
-    },
-    "purescript-overlay": {
-      "inputs": {
-        "flake-compat": "flake-compat",
-        "nixpkgs": [
-          "dream2nix",
-          "nixpkgs"
-        ],
-        "slimlock": "slimlock"
-      },
-      "locked": {
-        "lastModified": 1728546539,
-        "narHash": "sha256-Sws7w0tlnjD+Bjck1nv29NjC5DbL6nH5auL9Ex9Iz2A=",
-        "owner": "thomashoneyman",
-        "repo": "purescript-overlay",
-        "rev": "4ad4c15d07bd899d7346b331f377606631eb0ee4",
-        "type": "github"
-      },
-      "original": {
-        "owner": "thomashoneyman",
-        "repo": "purescript-overlay",
-        "type": "github"
-      }
-    },
-    "pyproject-nix": {
-      "inputs": {
-        "nixpkgs": [
-          "dream2nix",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1763017646,
-        "narHash": "sha256-Z+R2lveIp6Skn1VPH3taQIuMhABg1IizJd8oVdmdHsQ=",
-        "owner": "pyproject-nix",
-        "repo": "pyproject.nix",
-        "rev": "47bd6f296502842643078d66128f7b5e5370790c",
-        "type": "github"
-      },
-      "original": {
-        "owner": "pyproject-nix",
-        "repo": "pyproject.nix",
        "type": "github"
      }
    },
    "root": {
      "inputs": {
-        "crane": "crane",
-        "dream2nix": "dream2nix",
        "fenix": "fenix",
        "flake-parts": "flake-parts",
        "nixpkgs": "nixpkgs",
-        "nixpkgs-swift": "nixpkgs-swift",
        "treefmt-nix": "treefmt-nix"
      }
    },
    "rust-analyzer-src": {
      "flake": false,
      "locked": {
-        "lastModified": 1768224240,
-        "narHash": "sha256-Pp1dDrXKPBUJReZnnDElFyHYn67XTd48zRhToheLjtk=",
+        "lastModified": 1761849405,
+        "narHash": "sha256-igXdvC+WCUN+3gnfk+ptT7rMmxQuY6WbIg1rXMUN1DM=",
        "owner": "rust-lang",
        "repo": "rust-analyzer",
-        "rev": "725349602e525df37f377701e001fe8aab807878",
+        "rev": "f7de8ae045a5fe80f1203c5a1c3015b05f7c3550",
        "type": "github"
      },
      "original": {
@@ -198,28 +82,6 @@
        "type": "github"
      }
    },
-    "slimlock": {
-      "inputs": {
-        "nixpkgs": [
-          "dream2nix",
-          "purescript-overlay",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1688756706,
-        "narHash": "sha256-xzkkMv3neJJJ89zo3o2ojp7nFeaZc2G0fYwNXNJRFlo=",
-        "owner": "thomashoneyman",
-        "repo": "slimlock",
-        "rev": "cf72723f59e2340d24881fd7bf61cb113b4c407c",
-        "type": "github"
-      },
-      "original": {
-        "owner": "thomashoneyman",
-        "repo": "slimlock",
-        "type": "github"
-      }
-    },
    "treefmt-nix": {
      "inputs": {
        "nixpkgs": [
@@ -227,11 +89,11 @@
        ]
      },
      "locked": {
-        "lastModified": 1768158989,
-        "narHash": "sha256-67vyT1+xClLldnumAzCTBvU0jLZ1YBcf4vANRWP3+Ak=",
+        "lastModified": 1762938485,
+        "narHash": "sha256-AlEObg0syDl+Spi4LsZIBrjw+snSVU4T8MOeuZJUJjM=",
        "owner": "numtide",
        "repo": "treefmt-nix",
-        "rev": "e96d59dff5c0d7fddb9d113ba108f03c3ef99eca",
+        "rev": "5b4ee75aeefd1e2d5a1cc43cf6ba65eba75e83e4",
        "type": "github"
      },
      "original": {
--- a/flake.nix
+++ b/flake.nix
@@ -9,8 +9,6 @@
      inputs.nixpkgs-lib.follows = "nixpkgs";
    };

-    crane.url = "github:ipetkov/crane";
-
    fenix = {
      url = "github:nix-community/fenix";
      inputs.nixpkgs.follows = "nixpkgs";
@@ -20,14 +18,6 @@
      url = "github:numtide/treefmt-nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
-
-    dream2nix = {
-      url = "github:nix-community/dream2nix";
-      inputs.nixpkgs.follows = "nixpkgs";
-    };
-
-    # Pinned nixpkgs for swift-format (swift is broken on x86_64-linux in newer nixpkgs)
-    nixpkgs-swift.url = "github:NixOS/nixpkgs/08dacfca559e1d7da38f3cf05f1f45ee9bfd213c";
  };

  nixConfig = {
@@ -46,16 +36,12 @@

      imports = [
        inputs.treefmt-nix.flakeModule
-        ./dashboard/parts.nix
-        ./rust/parts.nix
      ];

      perSystem =
-        { config, self', inputs', pkgs, lib, system, ... }:
+        { config, inputs', pkgs, lib, ... }:
        let
          fenixToolchain = inputs'.fenix.packages.complete;
-          # Use pinned nixpkgs for swift-format (swift is broken on x86_64-linux in newer nixpkgs)
-          pkgsSwift = import inputs.nixpkgs-swift { inherit system; };
        in
        {
          treefmt = {
@@ -68,16 +54,13 @@
              };
              rustfmt = {
                enable = true;
-                package = config.rust.toolchain;
+                package = fenixToolchain.rustfmt;
              };
              prettier = {
                enable = true;
                includes = [ "*.ts" ];
              };
-              swift-format = {
-                enable = true;
-                package = pkgsSwift.swiftPackages.swift-format;
-              };
+              swift-format.enable = true;
            };
          };

@@ -87,9 +70,12 @@
            touch $out
          '';

-          devShells.default = with pkgs; pkgs.mkShell {
-            inputsFrom = [ self'.checks.cargo-build ];
+          packages =
+            if pkgs.stdenv.isDarwin then {
+              metal = pkgs.callPackage ./nix/metalWrapper.nix { metalVersion = "230"; };
+            } else { };

+          devShells.default = with pkgs; mkShellNoCC {
            packages =
              [
                # FORMATTING
@@ -102,8 +88,14 @@
                basedpyright

                # RUST
-                config.rust.toolchain
-                maturin
+                (fenixToolchain.withComponents [
+                  "cargo"
+                  "rustc"
+                  "clippy"
+                  "rustfmt"
+                  "rust-src"
+                ])
+                rustup # Just here to make RustRover happy

                # NIX
                nixpkgs-fmt
@@ -115,20 +107,31 @@
                just
                jq
              ]
-              ++ lib.optionals stdenv.isLinux [
+              ++ (lib.optionals stdenv.isLinux [
+                # IFCONFIG
                unixtools.ifconfig
-              ]
-              ++ lib.optionals stdenv.isDarwin [
-                macmon
-              ];

-            OPENSSL_NO_VENDOR = "1";
+                # Build dependencies for Linux
+                pkg-config
+                openssl
+              ])
+              ++ (lib.optionals stdenv.isDarwin [
+                # MACMON
+                macmon
+              ]);
+

            shellHook = ''
-              export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:${python313}/lib"
-              ${lib.optionalString stdenv.isLinux ''
-                export LD_LIBRARY_PATH="${openssl.out}/lib:$LD_LIBRARY_PATH"
+              # PYTHON
+              export LD_LIBRARY_PATH="$LD_LIBRARY_PATH:${pkgs.python313}/lib"
+              ${lib.optionalString pkgs.stdenv.isLinux ''
+                # Build environment for Linux
+                export PKG_CONFIG_PATH="${pkgs.openssl.dev}/lib/pkgconfig:$PKG_CONFIG_PATH"
+                export LD_LIBRARY_PATH="${pkgs.openssl.out}/lib:$LD_LIBRARY_PATH"
              ''}
+              echo
+              echo "🍎🍎 Run 'just <recipe>' to get started"
+              just --list
            '';
          };
        };
--- a/2
+++ b/2
@@ -1,5 +1,3 @@
-export NIX_CONFIG := "extra-experimental-features = nix-command flakes"
-
 fmt:
    nix fmt

--- a/nix/darwin-build-fixes.patch
+++ b/nix/darwin-build-fixes.patch
@@ -0,0 +1,79 @@
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 0ed30932..d8528132 100644
+--- a/CMakeLists.txt
+++ b/CMakeLists.txt
+@@ -177,11 +177,7 @@ if(MLX_BUILD_METAL)
+     add_compile_definitions(MLX_METAL_DEBUG)
+   endif()
+ 
+-  # Throw an error if xcrun not found
+-  execute_process(
+-    COMMAND zsh "-c" "/usr/bin/xcrun -sdk macosx --show-sdk-version"
+-    OUTPUT_VARIABLE MACOS_SDK_VERSION
+-    OUTPUT_STRIP_TRAILING_WHITESPACE COMMAND_ERROR_IS_FATAL ANY)
+  set(MACOS_SDK_VERSION @sdkVersion@)
+ 
+   if(${MACOS_SDK_VERSION} LESS 14.0)
+     message(
+@@ -199,11 +195,8 @@ if(MLX_BUILD_METAL)
+     endif()
+     set(XCRUN_FLAGS "-mmacosx-version-min=${CMAKE_OSX_DEPLOYMENT_TARGET}")
+   endif()
+-  execute_process(
+-    COMMAND
+-      zsh "-c"
+-      "echo \"__METAL_VERSION__\" | xcrun -sdk macosx metal ${XCRUN_FLAGS} -E -x metal -P - | tail -1 | tr -d '\n'"
+-    OUTPUT_VARIABLE MLX_METAL_VERSION COMMAND_ERROR_IS_FATAL ANY)
+  set(
+    MLX_METAL_VERSION @metalVersion@)
+   FetchContent_Declare(metal_cpp URL ${METAL_CPP_URL})
+   FetchContent_MakeAvailable(metal_cpp)
+   target_include_directories(
+diff --git a/cmake/extension.cmake b/cmake/extension.cmake
+index 13db804a..5b385132 100644
+--- a/cmake/extension.cmake
+++ b/cmake/extension.cmake
+@@ -36,7 +36,7 @@ macro(mlx_build_metallib)
+   add_custom_command(
+     OUTPUT ${MTLLIB_BUILD_TARGET}
+     COMMAND
+-      xcrun -sdk macosx metal
+      metal
+       "$<LIST:TRANSFORM,${MTLLIB_INCLUDE_DIRS},PREPEND,-I>"
+       ${MTLLIB_COMPILE_OPTIONS} ${MTLLIB_SOURCES} -o ${MTLLIB_BUILD_TARGET}
+     DEPENDS ${MTLLIB_DEPS} ${MTLLIB_SOURCES}
+diff --git a/mlx/backend/metal/kernels/CMakeLists.txt b/mlx/backend/metal/kernels/CMakeLists.txt
+index 262b0495..5c7446ad 100644
+--- a/mlx/backend/metal/kernels/CMakeLists.txt
+++ b/mlx/backend/metal/kernels/CMakeLists.txt
+@@ -29,7 +29,7 @@ function(build_kernel_base TARGET SRCFILE DEPS)
+                     "-mmacosx-version-min=${CMAKE_OSX_DEPLOYMENT_TARGET}")
+   endif()
+   add_custom_command(
+-    COMMAND xcrun -sdk macosx metal ${METAL_FLAGS} -c ${SRCFILE}
+    COMMAND metal ${METAL_FLAGS} -c ${SRCFILE}
+             -I${PROJECT_SOURCE_DIR} -o ${TARGET}.air
+     DEPENDS ${SRCFILE} ${DEPS} ${BASE_HEADERS}
+     OUTPUT ${TARGET}.air
+@@ -170,7 +170,7 @@ endif()
+ 
+ add_custom_command(
+   OUTPUT ${MLX_METAL_PATH}/mlx.metallib
+-  COMMAND xcrun -sdk macosx metallib ${KERNEL_AIR} -o
+  COMMAND metallib ${KERNEL_AIR} -o
+           ${MLX_METAL_PATH}/mlx.metallib
+   DEPENDS ${KERNEL_AIR}
+   COMMENT "Building mlx.metallib"
+diff --git a/mlx/backend/metal/make_compiled_preamble.sh b/mlx/backend/metal/make_compiled_preamble.sh
+index bb55ed3a..94ea7dd7 100644
+--- a/mlx/backend/metal/make_compiled_preamble.sh
+++ b/mlx/backend/metal/make_compiled_preamble.sh
+@@ -31,7 +31,7 @@ OUTPUT_FILE=${OUTPUT_DIR}/${SRC_NAME}.cpp
+ mkdir -p "$OUTPUT_DIR"
+ 
+ # Use the metal compiler to get a list of headers (with depth)
+-CCC="xcrun -sdk macosx metal -x metal"
+CCC="metal -x metal"
+ HDRS=$( $CCC -I"$SRC_DIR" -I"$JIT_INCLUDES" -DMLX_METAL_JIT -E -P -CC -C -H "$INPUT_FILE" $CFLAGS -w 2>&1 1>/dev/null )
+ 
+ # Remove any included system frameworks (for MetalPerformancePrimitive headers)
--- a/nix/metalWrapper.nix
+++ b/nix/metalWrapper.nix
@@ -0,0 +1,22 @@
+{ stdenv
+, metalVersion
+, xcodeBaseDir ? "/Applications/Xcode.app"
+}:
+assert stdenv.isDarwin;
+stdenv.mkDerivation {
+  pname = "metal-wrapper-impure";
+  version = metalVersion;
+
+  __noChroot = true;
+  buildCommand = ''
+    DEVELOPER_DIR=${xcodeBaseDir}/Contents/Developer
+    [[ -x "$DEVELOPER_DIR/usr/bin/xcodebuild" ]] || (echo "Missing xcodebuild at $DEVELOPER_DIR/usr/bin/xcodebuild" && exit 1)
+    SDKROOT=${xcodeBaseDir}/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk
+    [[ -d "$SDKROOT" ]] || (echo "Missing SDKROOT at $SDKROOT" && exit 1)
+    export DEVELOPER_DIR SDKROOT
+    mkdir -p $out/bin && cd $out/bin
+    ln -s $(/usr/bin/xcrun --sdk macosx -f metal)
+    ln -s $(/usr/bin/xcrun --sdk macosx -f metallib)
+    [[ -f $out/bin/metal ]] && [[ -f $out/bin/metallib ]] || exit 1
+  '';
+}
--- a/nix/mlx.nix
+++ b/nix/mlx.nix
@@ -0,0 +1,154 @@
+{ stdenv
+, lib
+, buildPythonPackage
+, fetchFromGitHub
+, replaceVars
+, fetchzip
+, setuptools
+, cmake
+, nanobind
+, pybind11
+, nlohmann_json
+, apple-sdk_26
+, metal
+, numpy
+, pytestCheckHook
+, python
+, runCommand
+, fmt
+}:
+assert stdenv.isDarwin;
+let
+  # static dependencies included directly during compilation
+  gguf-tools = fetchFromGitHub {
+    owner = "antirez";
+    repo = "gguf-tools";
+    rev = "8fa6eb65236618e28fd7710a0fba565f7faa1848";
+    hash = "sha256-15FvyPOFqTOr5vdWQoPnZz+mYH919++EtghjozDlnSA=";
+  };
+
+  metal_cpp = fetchzip {
+    url = "https://developer.apple.com/metal/cpp/files/metal-cpp_26.zip";
+    hash = "sha256-7n2eI2lw/S+Us6l7YPAATKwcIbRRpaQ8VmES7S8ZjY8=";
+  };
+
+  mlx = buildPythonPackage rec {
+    pname = "mlx";
+    version = "0.30.1";
+    pyproject = true;
+
+    src = fetchFromGitHub {
+      owner = "ml-explore";
+      repo = "mlx";
+      tag = "v${version}";
+      hash = "sha256-Vt0RH+70VBwUjXSfPTsNdRS3g0ookJHhzf2kvgEtgH8=";
+    };
+
+    patches = [
+      (replaceVars ./darwin-build-fixes.patch {
+        sdkVersion = apple-sdk_26.version;
+        metalVersion = metal.version;
+      })
+    ];
+
+    postPatch = ''
+      substituteInPlace pyproject.toml \
+        --replace-fail "nanobind==2.10.2" "nanobind"
+
+      substituteInPlace mlx/backend/cpu/jit_compiler.cpp \
+        --replace-fail "g++" "$CXX"
+    '';
+
+    dontUseCmakeConfigure = true;
+
+    enableParallelBuilding = true;
+
+    # Allows multiple cores to be used in Python builds.
+    postUnpack = ''
+      export MAKEFLAGS+="''${enableParallelBuilding:+-j$NIX_BUILD_CORES}"
+    '';
+
+    # updates the wrong fetcher rev attribute
+    passthru.skipBulkUpdate = true;
+
+    env = {
+      DEV_RELEASE = 1;
+      # NOTE The `metal` command-line utility used to build the Metal kernels is not open-source.
+      # this is what the xcode wrapper is for - it patches in the system metal cli
+      CMAKE_ARGS = toString [
+        (lib.cmakeBool "USE_SYSTEM_FMT" true)
+        (lib.cmakeOptionType "filepath" "FETCHCONTENT_SOURCE_DIR_GGUFLIB" "${gguf-tools}")
+        (lib.cmakeOptionType "filepath" "FETCHCONTENT_SOURCE_DIR_JSON" "${nlohmann_json.src}")
+        (lib.cmakeBool "FETCHCONTENT_FULLY_DISCONNECTED" true)
+        (lib.cmakeBool "MLX_BUILD_METAL" true)
+        (lib.cmakeOptionType "filepath" "METAL_LIB"
+          "${metal}/Metal.framework")
+        (lib.cmakeOptionType "filepath" "FETCHCONTENT_SOURCE_DIR_METAL_CPP" "${metal_cpp}")
+        (lib.cmakeOptionType "string" "CMAKE_OSX_DEPLOYMENT_TARGET" "${apple-sdk_26.version}")
+        (lib.cmakeOptionType "filepath" "CMAKE_OSX_SYSROOT" "${apple-sdk_26.passthru.sdkroot}")
+      ];
+      SDKROOT = apple-sdk_26.passthru.sdkroot;
+      MACOSX_DEPLOYMENT_TARGET = apple-sdk_26.version;
+    };
+
+    build-system = [
+      setuptools
+    ];
+
+    nativeBuildInputs = [
+      cmake
+      metal
+    ];
+
+    buildInputs = [
+      fmt
+      gguf-tools
+      nanobind
+      pybind11
+      apple-sdk_26
+    ];
+
+    pythonImportsCheck = [ "mlx" ];
+
+    # Run the mlx Python test suite.
+    nativeCheckInputs = [
+      numpy
+      pytestCheckHook
+    ];
+
+    enabledTestPaths = [
+      "python/tests/"
+    ];
+
+    # Additional testing by executing the example Python scripts supplied with mlx
+    # using the version of the library we've built.
+    passthru.tests = {
+      mlxTest =
+        runCommand "run-mlx-examples"
+          {
+            buildInputs = [ mlx ];
+            nativeBuildInputs = [ python ];
+          }
+          ''
+            cp ${src}/examples/python/logistic_regression.py .
+            ${python.interpreter} logistic_regression.py
+            rm logistic_regression.py
+
+            cp ${src}/examples/python/linear_regression.py .
+            ${python.interpreter} linear_regression.py
+            rm linear_regression.py
+
+            touch $out
+          '';
+    };
+
+    meta = {
+      homepage = "https://github.com/ml-explore/mlx";
+      description = "Array framework for Apple silicon";
+      changelog = "https://github.com/ml-explore/mlx/releases/tag/${src.tag}";
+      license = lib.licenses.mit;
+      platforms = [ "x86_64-linux" "aarch64-linux" "aarch64-darwin" ];
+    };
+  };
+in
+mlx
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -23,7 +23,6 @@ dependencies = [
    "tiktoken>=0.12.0", # required for kimi k2 tokenizer
    "hypercorn>=0.18.0",
    "openai-harmony>=0.0.8",
-    "httpx>=0.28.1",
 ]

 [project.scripts]
--- a/rust/parts.nix
+++ b/rust/parts.nix
@@ -1,145 +0,0 @@
-{ inputs, ... }:
-{
-  perSystem =
-    { config, self', inputs', pkgs, lib, ... }:
-    let
-      # Fenix nightly toolchain with all components
-      fenixPkgs = inputs'.fenix.packages;
-      rustToolchain = fenixPkgs.complete.withComponents [
-        "cargo"
-        "rustc"
-        "clippy"
-        "rustfmt"
-        "rust-src"
-        "rust-analyzer"
-      ];
-
-      # Crane with fenix toolchain
-      craneLib = (inputs.crane.mkLib pkgs).overrideToolchain rustToolchain;
-
-      # Source filtering - only include rust/ directory and root Cargo files
-      # This ensures changes to Python/docs/etc don't trigger Rust rebuilds
-      src = lib.cleanSourceWith {
-        src = inputs.self;
-        filter =
-          path: type:
-          let
-            baseName = builtins.baseNameOf path;
-            parentDir = builtins.dirOf path;
-            inRustDir =
-              (lib.hasInfix "/rust/" path)
-              || (lib.hasSuffix "/rust" parentDir)
-              || (baseName == "rust" && type == "directory");
-            isRootCargoFile =
-              (baseName == "Cargo.toml" || baseName == "Cargo.lock")
-              && (builtins.dirOf path == toString inputs.self);
-          in
-          isRootCargoFile
-          || (inRustDir && (craneLib.filterCargoSources path type || lib.hasSuffix ".toml" path || lib.hasSuffix ".md" path));
-      };
-
-      # Common arguments for all Rust builds
-      commonArgs = {
-        inherit src;
-        pname = "exo-rust";
-        version = "0.0.1";
-        strictDeps = true;
-
-        nativeBuildInputs = [
-          pkgs.pkg-config
-          pkgs.python313 # Required for pyo3-build-config
-        ];
-
-        buildInputs = [
-          pkgs.openssl
-          pkgs.python313 # Required for pyo3 tests
-        ];
-
-        OPENSSL_NO_VENDOR = "1";
-
-        # Required for pyo3 tests to find libpython
-        LD_LIBRARY_PATH = lib.makeLibraryPath [ pkgs.python313 ];
-      };
-
-      # Build dependencies once for caching
-      cargoArtifacts = craneLib.buildDepsOnly (
-        commonArgs
-        // {
-          cargoExtraArgs = "--workspace";
-        }
-      );
-    in
-    {
-      # Export toolchain for use in treefmt and devShell
-      options.rust = {
-        toolchain = lib.mkOption {
-          type = lib.types.package;
-          default = rustToolchain;
-          description = "The Rust toolchain to use";
-        };
-      };
-
-      config = {
-        packages = {
-          # Python bindings wheel via maturin
-          exo_pyo3_bindings = craneLib.buildPackage (
-            commonArgs
-            // {
-              inherit cargoArtifacts;
-              pname = "exo_pyo3_bindings";
-
-              nativeBuildInputs = commonArgs.nativeBuildInputs ++ [
-                pkgs.maturin
-              ];
-
-              buildPhaseCargoCommand = ''
-                maturin build \
-                  --release \
-                  --manylinux off \
-                  --manifest-path rust/exo_pyo3_bindings/Cargo.toml \
-                  --features "pyo3/extension-module,pyo3/experimental-async" \
-                  --interpreter ${pkgs.python313}/bin/python \
-                  --out dist
-              '';
-
-              # Don't use crane's default install behavior
-              doNotPostBuildInstallCargoBinaries = true;
-
-              installPhaseCommand = ''
-                mkdir -p $out
-                cp dist/*.whl $out/
-              '';
-            }
-          );
-        };
-
-        checks = {
-          # Full workspace build (all crates)
-          cargo-build = craneLib.buildPackage (
-            commonArgs
-            // {
-              inherit cargoArtifacts;
-              cargoExtraArgs = "--workspace";
-            }
-          );
-          # Run tests with nextest
-          cargo-nextest = craneLib.cargoNextest (
-            commonArgs
-            // {
-              inherit cargoArtifacts;
-              cargoExtraArgs = "--workspace";
-            }
-          );
-
-          # Build documentation
-          cargo-doc = craneLib.cargoDoc (
-            commonArgs
-            // {
-              inherit cargoArtifacts;
-              cargoExtraArgs = "--workspace";
-            }
-          );
-        };
-      };
-    };
-}
--- a/rust/system_custodian/Cargo.toml
+++ b/rust/system_custodian/Cargo.toml
@@ -0,0 +1,47 @@
+[package]
+name = "system_custodian"
+version = { workspace = true }
+edition = { workspace = true }
+publish = false
+
+[lib]
+doctest = false
+name = "system_custodian"
+path = "src/lib.rs"
+
+[[bin]]
+path = "src/bin/main.rs"
+name = "system_custodian"
+doc = false
+
+[lints]
+workspace = true
+
+[dependencies]
+# datastructures
+either = { workspace = true }
+
+# macro dependencies
+extend = { workspace = true }
+delegate = { workspace = true }
+impl-trait-for-tuples = { workspace = true }
+derive_more = { workspace = true }
+
+# async
+tokio = { workspace = true, features = ["full"] }
+futures = { workspace = true }
+futures-timer = { workspace = true }
+
+# utility dependencies
+util = { workspace = true }
+thiserror = { workspace = true }
+#internment = { workspace = true }
+#recursion = { workspace = true }
+#generativity = { workspace = true }
+#itertools = { workspace = true }
+tracing-subscriber = { version = "0.3.19", features = ["default", "env-filter"] }
+keccak-const = { workspace = true }
+
+# tracing/logging
+log = { workspace = true }
+
--- a/rust/system_custodian/src/bin/main.rs
+++ b/rust/system_custodian/src/bin/main.rs
@@ -0,0 +1,4 @@
+//! TODO: documentation
+//!
+
+fn main() {}
--- a/rust/system_custodian/src/lib.rs
+++ b/rust/system_custodian/src/lib.rs
@@ -0,0 +1,69 @@
+//! This crate defines the logic of, and ways to interact with, Exo's **_System Custodian_** daemon.
+//!
+//! The **_System Custodian_** daemon is supposed to be a long-living process that precedes the
+//! launch of the Exo application, and responsible for ensuring the system (configuration, settings,
+//! etc.) is in an appropriate state to facilitate the running of Exo application.
+//! The **_System Custodian_** daemon shall expose a [D-Bus](https://www.freedesktop.org/wiki/Software/dbus/)
+//! service which Exo application use to _control & query_ it.
+//!
+//! # Lifecycle
+//! When the Exo application starts, it will _wake_ the **_System Custodian_** daemon for the
+//! duration of its lifetime, and after it has terminated the daemon will go back to sleep. When
+//! the daemon wakes up, it will configure the system into a state suitable for the Exo Application;
+//! When the daemon goes to sleep, it will revert those changes as much as it can in case they were
+//! destructive to the user's pre-existing configurations.
+//!
+//! # Responsibilities
+//! TODO: these are purely on MacOS, but change to be more broad
+//! The **_System Custodian_** daemon is responsible for using System Configuration framework to
+//!  1. duplicate the current network set
+//!  2. modify existing services to turn on IPv6 if not there
+//!  3. remove any bridge services & add any missing services that AREN'T bridge
+//! TODO: In the future:
+//!  1. run a dummy AWDL service to [allow for macOS peer-to-peer wireless networking](https://yggdrasil-network.github.io/2019/08/19/awdl.html)
+//!  2. toggle some GPU/memory configurations to speed up GPU (ask Alex what those configurations are)
+//!  3. if we ever decide to provide our **own network interfaces** that abstract over some userland
+//!     logic, this would be the place to spin that up.
+//!
+//! Then it will watch the SCDynamicStore for:
+//!  1. all __actual__ network interfaces -> collect information on them e.g. their BSD name, MAC
+//!     address, MTU, IPv6 addresses, etc. -> and set up watchers/notifiers to inform the DBus
+//!     interface of any changes
+//!  2. watch for any __undesirable__ changes to configuration and revert it
+//!
+//! It should somehow (probably through system sockets and/or BSD interface) trigger IPv6 NDP on
+//! each of the interfaces & also listen to/query for any changes on the OS routing cache??
+//! Basically emulate the `ping6 ff02::1%enX` and `ndp -an` commands BUT BETTER!!!
+//!  1. all that info should coalesce back to the overall state colleted -> should be queryable
+//!     over D-Bus
+//! TODO:
+//!  1. we might potentially add to this step a handshake of some kind...? To ensure that we can
+//!     ACTUALLY communicate with that machine over that link over e.g. TCP, UDP, etc. Will the
+//!     handshake require to know Node ID? Will the handshake require heartbeats? Who knows...
+//!  2. if we ever decide to write proprietary L2/L3 protocols for quicker communication,
+//!     e.g. [AF_NDRV](https://www.zerotier.com/blog/how-zerotier-eliminated-kernel-extensions-on-macos/)
+//!     for raw ethernet frame communication, or even a [custom thunderbolt PCIe driver](https://developer.apple.com/documentation/pcidriverkit/creating-custom-pcie-drivers-for-thunderbolt-devices),
+//!     then this would be the place to carry out discovery and propper handshakes with devices
+//!     on the other end of the link.
+//!
+
+// enable Rust-unstable features for convenience
+#![feature(trait_alias)]
+#![feature(stmt_expr_attributes)]
+#![feature(type_alias_impl_trait)]
+#![feature(specialization)]
+#![feature(unboxed_closures)]
+#![feature(const_trait_impl)]
+#![feature(fn_traits)]
+
+pub(crate) mod private {
+    // sealed traits support
+    pub trait Sealed {}
+    impl<T: ?Sized> Sealed for T {}
+}
+
+/// Namespace for all the type/trait aliases used by this crate.
+pub(crate) mod alias {}
+
+/// Namespace for crate-wide extension traits/methods
+pub(crate) mod ext {}
--- a/src/exo/main.py
+++ b/src/exo/main.py
@@ -205,14 +205,6 @@ def main():
    logger.info("Starting EXO")
    logger.info(f"EXO_LIBP2P_NAMESPACE: {os.getenv('EXO_LIBP2P_NAMESPACE')}")

-    # Set FAST_SYNCH override env var for runner subprocesses
-    if args.fast_synch is True:
-        os.environ["EXO_FAST_SYNCH"] = "on"
-        logger.info("FAST_SYNCH forced ON")
-    elif args.fast_synch is False:
-        os.environ["EXO_FAST_SYNCH"] = "off"
-        logger.info("FAST_SYNCH forced OFF")
-
    node = anyio.run(Node.create, args)
    anyio.run(node.run)
    logger.info("EXO Shutdown complete")
@@ -226,7 +218,6 @@ class Args(CamelCaseModel):
    api_port: PositiveInt = 52415
    tb_only: bool = False
    no_worker: bool = False
-    fast_synch: bool | None = None  # None = auto, True = force on, False = force off

    @classmethod
    def parse(cls) -> Self:
@@ -268,20 +259,6 @@ class Args(CamelCaseModel):
            "--no-worker",
            action="store_true",
        )
-        fast_synch_group = parser.add_mutually_exclusive_group()
-        fast_synch_group.add_argument(
-            "--fast-synch",
-            action="store_true",
-            dest="fast_synch",
-            default=None,
-            help="Force MLX FAST_SYNCH on (for JACCL backend)",
-        )
-        fast_synch_group.add_argument(
-            "--no-fast-synch",
-            action="store_false",
-            dest="fast_synch",
-            help="Force MLX FAST_SYNCH off",
-        )

        args = parser.parse_args()
        return cls(**vars(args))  # pyright: ignore[reportAny] - We are intentionally validating here, we can't do it statically
--- a/src/exo/master/api.py
+++ b/src/exo/master/api.py
@@ -1,19 +1,24 @@
 import time
 from collections.abc import AsyncGenerator
-from http import HTTPStatus
 from typing import cast

 import anyio
-from anyio import BrokenResourceError, create_task_group
+from anyio import create_task_group
 from anyio.abc import TaskGroup
-from fastapi import FastAPI, HTTPException, Request
+from fastapi import FastAPI, HTTPException
 from fastapi.middleware.cors import CORSMiddleware
-from fastapi.responses import JSONResponse, StreamingResponse
+from fastapi.responses import StreamingResponse
 from fastapi.staticfiles import StaticFiles
 from hypercorn.asyncio import serve  # pyright: ignore[reportUnknownVariableType]
 from hypercorn.config import Config
 from hypercorn.typing import ASGIFramework
 from loguru import logger
+from openai_harmony import (  # pyright: ignore[reportMissingTypeStubs]
+    HarmonyEncodingName,
+    Role,
+    StreamableParser,
+    load_harmony_encoding,
+)

 from exo.master.placement import place_instance as get_instance_placements
 from exo.shared.apply import apply
@@ -30,8 +35,6 @@ from exo.shared.types.api import (
    CreateInstanceParams,
    CreateInstanceResponse,
    DeleteInstanceResponse,
-    ErrorInfo,
-    ErrorResponse,
    FinishReason,
    GenerationStats,
    ModelList,
@@ -52,12 +55,7 @@ from exo.shared.types.commands import (
    TaskFinished,
 )
 from exo.shared.types.common import CommandId, NodeId, SessionId
-from exo.shared.types.events import (
-    ChunkGenerated,
-    Event,
-    ForwarderEvent,
-    IndexedEvent,
-)
+from exo.shared.types.events import ChunkGenerated, Event, ForwarderEvent, IndexedEvent
 from exo.shared.types.memory import Memory
 from exo.shared.types.models import ModelId, ModelMetadata
 from exo.shared.types.state import State
@@ -69,6 +67,8 @@ from exo.utils.channels import Receiver, Sender, channel
 from exo.utils.dashboard_path import find_dashboard
 from exo.utils.event_buffer import OrderedBuffer

+encoding = load_harmony_encoding(HarmonyEncodingName.HARMONY_GPT_OSS)
+

 def chunk_to_response(
    chunk: TokenChunk, command_id: CommandId
@@ -123,7 +123,6 @@ class API:
        self.paused_ev: anyio.Event = anyio.Event()

        self.app = FastAPI()
-        self._setup_exception_handlers()
        self._setup_cors()
        self._setup_routes()

@@ -154,20 +153,6 @@ class API:
        self.paused_ev.set()
        self.paused_ev = anyio.Event()

-    def _setup_exception_handlers(self) -> None:
-        @self.app.exception_handler(HTTPException)
-        async def http_exception_handler(  # pyright: ignore[reportUnusedFunction]
-            _: Request, exc: HTTPException
-        ) -> JSONResponse:
-            err = ErrorResponse(
-                error=ErrorInfo(
-                    message=exc.detail,
-                    type=HTTPStatus(exc.status_code).phrase,
-                    code=exc.status_code,
-                )
-            )
-            return JSONResponse(err.model_dump(), status_code=exc.status_code)
-
    def _setup_cors(self) -> None:
        self.app.add_middleware(
            CORSMiddleware,
@@ -200,8 +185,6 @@ class API:
            sharding=payload.sharding,
            instance_meta=payload.instance_meta,
            min_nodes=payload.min_nodes,
-            draft_model=payload.draft_model,
-            num_draft_tokens=payload.num_draft_tokens,
        )
        await self._send(command)

@@ -398,8 +381,35 @@ class API:
            instance_id=instance_id,
        )

+    async def _process_gpt_oss(self, token_chunks: Receiver[TokenChunk]):
+        stream = StreamableParser(encoding, role=Role.ASSISTANT)
+        thinking = False
+
+        async for chunk in token_chunks:
+            stream.process(chunk.token_id)
+
+            delta = stream.last_content_delta
+            ch = stream.current_channel
+
+            if ch == "analysis" and not thinking:
+                thinking = True
+                yield chunk.model_copy(update={"text": "<think>"})
+
+            if ch != "analysis" and thinking:
+                thinking = False
+                yield chunk.model_copy(update={"text": "</think>"})
+
+            if delta:
+                yield chunk.model_copy(update={"text": delta})
+
+            if chunk.finish_reason is not None:
+                if thinking:
+                    yield chunk.model_copy(update={"text": "</think>"})
+                yield chunk
+                break
+
    async def _chat_chunk_stream(
-        self, command_id: CommandId
+        self, command_id: CommandId, parse_gpt_oss: bool
    ) -> AsyncGenerator[TokenChunk, None]:
        """Yield `TokenChunk`s for a given command until completion."""

@@ -407,10 +417,16 @@ class API:
            self._chat_completion_queues[command_id], recv = channel[TokenChunk]()

            with recv as token_chunks:
-                async for chunk in token_chunks:
-                    yield chunk
-                    if chunk.finish_reason is not None:
-                        break
+                if parse_gpt_oss:
+                    async for chunk in self._process_gpt_oss(token_chunks):
+                        yield chunk
+                        if chunk.finish_reason is not None:
+                            break
+                else:
+                    async for chunk in token_chunks:
+                        yield chunk
+                        if chunk.finish_reason is not None:
+                            break

        except anyio.get_cancelled_exc_class():
            # TODO: TaskCancelled
@@ -426,23 +442,11 @@ class API:
            del self._chat_completion_queues[command_id]

    async def _generate_chat_stream(
-        self, command_id: CommandId
+        self, command_id: CommandId, parse_gpt_oss: bool
    ) -> AsyncGenerator[str, None]:
        """Generate chat completion stream as JSON strings."""

-        async for chunk in self._chat_chunk_stream(command_id):
-            if chunk.finish_reason == "error":
-                error_response = ErrorResponse(
-                    error=ErrorInfo(
-                        message=chunk.error_message or "Internal server error",
-                        type="InternalServerError",
-                        code=500,
-                    )
-                )
-                yield f"data: {error_response.model_dump_json()}\n\n"
-                yield "data: [DONE]\n\n"
-                return
-
+        async for chunk in self._chat_chunk_stream(command_id, parse_gpt_oss):
            chunk_response: ChatCompletionResponse = chunk_to_response(
                chunk, command_id
            )
@@ -454,7 +458,7 @@ class API:
                yield "data: [DONE]\n\n"

    async def _collect_chat_completion(
-        self, command_id: CommandId
+        self, command_id: CommandId, parse_gpt_oss: bool
    ) -> ChatCompletionResponse:
        """Collect all token chunks for a chat completion and return a single response."""

@@ -462,13 +466,7 @@ class API:
        model: str | None = None
        finish_reason: FinishReason | None = None

-        async for chunk in self._chat_chunk_stream(command_id):
-            if chunk.finish_reason == "error":
-                raise HTTPException(
-                    status_code=500,
-                    detail=chunk.error_message or "Internal server error",
-                )
-
+        async for chunk in self._chat_chunk_stream(command_id, parse_gpt_oss):
            if model is None:
                model = chunk.model

@@ -497,7 +495,7 @@ class API:
        )

    async def _collect_chat_completion_with_stats(
-        self, command_id: CommandId
+        self, command_id: CommandId, parse_gpt_oss: bool
    ) -> BenchChatCompletionResponse:
        text_parts: list[str] = []
        model: str | None = None
@@ -505,13 +503,7 @@ class API:

        stats: GenerationStats | None = None

-        async for chunk in self._chat_chunk_stream(command_id):
-            if chunk.finish_reason == "error":
-                raise HTTPException(
-                    status_code=500,
-                    detail=chunk.error_message or "Internal server error",
-                )
-
+        async for chunk in self._chat_chunk_stream(command_id, parse_gpt_oss):
            if model is None:
                model = chunk.model

@@ -552,6 +544,8 @@ class API:
        """Handle chat completions, supporting both streaming and non-streaming responses."""
        model_meta = await resolve_model_meta(payload.model)
        payload.model = model_meta.model_id
+        parse_gpt_oss = "gpt-oss" in model_meta.model_id.lower()
+        logger.info(f"{parse_gpt_oss=}")

        if not any(
            instance.shard_assignments.model_id == payload.model
@@ -568,16 +562,17 @@ class API:
        await self._send(command)
        if payload.stream:
            return StreamingResponse(
-                self._generate_chat_stream(command.command_id),
+                self._generate_chat_stream(command.command_id, parse_gpt_oss),
                media_type="text/event-stream",
            )

-        return await self._collect_chat_completion(command.command_id)
+        return await self._collect_chat_completion(command.command_id, parse_gpt_oss)

    async def bench_chat_completions(
        self, payload: BenchChatCompletionTaskParams
    ) -> BenchChatCompletionResponse:
        model_meta = await resolve_model_meta(payload.model)
+        parse_gpt_oss = "gpt-oss" in model_meta.model_id.lower()
        payload.model = model_meta.model_id

        if not any(
@@ -594,7 +589,10 @@ class API:
        command = ChatCompletion(request_params=payload)
        await self._send(command)

-        response = await self._collect_chat_completion_with_stats(command.command_id)
+        response = await self._collect_chat_completion_with_stats(
+            command.command_id,
+            parse_gpt_oss,
+        )
        return response

    def _calculate_total_available_memory(self) -> Memory:
@@ -656,14 +654,14 @@ class API:
                for idx, event in self.event_buffer.drain_indexed():
                    self._event_log.append(event)
                    self.state = apply(self.state, IndexedEvent(event=event, idx=idx))
-                    if isinstance(event, ChunkGenerated):
+                    if (
+                        isinstance(event, ChunkGenerated)
+                        and event.command_id in self._chat_completion_queues
+                    ):
                        assert isinstance(event.chunk, TokenChunk)
-                        queue = self._chat_completion_queues.get(event.command_id)
-                        if queue is not None:
-                            try:
-                                await queue.send(event.chunk)
-                            except BrokenResourceError:
-                                self._chat_completion_queues.pop(event.command_id, None)
+                        await self._chat_completion_queues[event.command_id].send(
+                            event.chunk
+                        )

    async def _pause_on_new_election(self):
        with self.election_receiver as ems:
--- a/src/exo/master/placement.py
+++ b/src/exo/master/placement.py
@@ -151,8 +151,6 @@ def place_instance(
                shard_assignments=shard_assignments,
                ibv_devices=mlx_ibv_devices,
                jaccl_coordinators=mlx_jaccl_coordinators,
-                draft_model=command.draft_model,
-                num_draft_tokens=command.num_draft_tokens,
            )
        case InstanceMeta.MlxRing:
            ephemeral_port = random_ephemeral_port()
@@ -166,8 +164,6 @@ def place_instance(
                shard_assignments=shard_assignments,
                hosts_by_node=hosts_by_node,
                ephemeral_port=ephemeral_port,
-                draft_model=command.draft_model,
-                num_draft_tokens=command.num_draft_tokens,
            )

    return target_instances
--- a/src/exo/master/tests/test_api_error_handling.py
+++ b/src/exo/master/tests/test_api_error_handling.py
@@ -1,107 +0,0 @@
-# pyright: reportUnusedFunction=false, reportAny=false
-from typing import Any, get_args
-
-from fastapi import FastAPI, HTTPException
-from fastapi.testclient import TestClient
-
-from exo.shared.types.api import ErrorInfo, ErrorResponse, FinishReason
-from exo.shared.types.chunks import TokenChunk
-from exo.worker.tests.constants import MODEL_A_ID
-
-
-def test_http_exception_handler_formats_openai_style() -> None:
-    """Test that HTTPException is converted to OpenAI-style error format."""
-    from exo.master.api import API
-
-    app = FastAPI()
-
-    # Setup exception handler
-    api = object.__new__(API)
-    api.app = app
-    api._setup_exception_handlers()  # pyright: ignore[reportPrivateUsage]
-
-    # Add test routes that raise HTTPException
-    @app.get("/test-error")
-    async def _test_error() -> None:
-        raise HTTPException(status_code=500, detail="Test error message")
-
-    @app.get("/test-not-found")
-    async def _test_not_found() -> None:
-        raise HTTPException(status_code=404, detail="Resource not found")
-
-    client = TestClient(app)
-
-    # Test 500 error
-    response = client.get("/test-error")
-    assert response.status_code == 500
-    data: dict[str, Any] = response.json()
-    assert "error" in data
-    assert data["error"]["message"] == "Test error message"
-    assert data["error"]["type"] == "Internal Server Error"
-    assert data["error"]["code"] == 500
-
-    # Test 404 error
-    response = client.get("/test-not-found")
-    assert response.status_code == 404
-    data = response.json()
-    assert "error" in data
-    assert data["error"]["message"] == "Resource not found"
-    assert data["error"]["type"] == "Not Found"
-    assert data["error"]["code"] == 404
-
-
-def test_finish_reason_includes_error() -> None:
-    valid_reasons = get_args(FinishReason)
-    assert "error" in valid_reasons
-
-
-def test_token_chunk_with_error_fields() -> None:
-    chunk = TokenChunk(
-        idx=0,
-        model=MODEL_A_ID,
-        text="",
-        token_id=0,
-        finish_reason="error",
-        error_message="Something went wrong",
-    )
-
-    assert chunk.finish_reason == "error"
-    assert chunk.error_message == "Something went wrong"
-
-
-def test_token_chunk_without_error() -> None:
-    chunk = TokenChunk(
-        idx=1,
-        model=MODEL_A_ID,
-        text="Hello",
-        token_id=42,
-        finish_reason=None,
-    )
-
-    assert chunk.finish_reason is None
-    assert chunk.error_message is None
-
-
-def test_error_response_construction() -> None:
-    error_response = ErrorResponse(
-        error=ErrorInfo(
-            message="Generation failed",
-            type="InternalServerError",
-            code=500,
-        )
-    )
-
-    assert error_response.error.message == "Generation failed"
-    assert error_response.error.code == 500
-
-
-def test_normal_finish_reasons_still_work() -> None:
-    for reason in ["stop", "length", "tool_calls", "content_filter", "function_call"]:
-        chunk = TokenChunk(
-            idx=0,
-            model=MODEL_A_ID,
-            text="done",
-            token_id=100,
-            finish_reason=reason,  # type: ignore[arg-type]
-        )
-        assert chunk.finish_reason == reason
--- a/src/exo/shared/logging.py
+++ b/src/exo/shared/logging.py
@@ -29,11 +29,6 @@ class _InterceptHandler(logging.Handler):

 def logger_setup(log_file: Path | None, verbosity: int = 0):
    """Set up logging for this process - formatting, file handles, verbosity and output"""
-
-    logging.getLogger("exo_pyo3_bindings").setLevel(logging.WARNING)
-    logging.getLogger("httpx").setLevel(logging.WARNING)
-    logging.getLogger("httpcore").setLevel(logging.WARNING)
-
    logger.remove()

    # replace all stdlib loggers with _InterceptHandlers that log to loguru
--- a/src/exo/shared/models/model_cards.py
+++ b/src/exo/shared/models/model_cards.py
@@ -14,6 +14,32 @@ class ModelCard(CamelCaseModel):

 MODEL_CARDS: dict[str, ModelCard] = {
    # deepseek v3
+    # "deepseek-v3-0324:4bit": ModelCard(
+    #     short_id="deepseek-v3-0324:4bit",
+    #     model_id="mlx-community/DeepSeek-V3-0324-4bit",
+    #     name="DeepSeek V3 0324 (4-bit)",
+    #     description="""DeepSeek V3 is a large language model trained on the DeepSeek V3 dataset.""",
+    #     tags=[],
+    #     metadata=ModelMetadata(
+    #         model_id=ModelId("mlx-community/DeepSeek-V3-0324-4bit"),
+    #         pretty_name="DeepSeek V3 0324 (4-bit)",
+    #         storage_size=Memory.from_kb(409706307),
+    #         n_layers=61,
+    #     ),
+    # ),
+    # "deepseek-v3-0324": ModelCard(
+    #     short_id="deepseek-v3-0324",
+    #     model_id="mlx-community/DeepSeek-v3-0324-8bit",
+    #     name="DeepSeek V3 0324 (8-bit)",
+    #     description="""DeepSeek V3 is a large language model trained on the DeepSeek V3 dataset.""",
+    #     tags=[],
+    #     metadata=ModelMetadata(
+    #         model_id=ModelId("mlx-community/DeepSeek-v3-0324-8bit"),
+    #         pretty_name="DeepSeek V3 0324 (8-bit)",
+    #         storage_size=Memory.from_kb(754706307),
+    #         n_layers=61,
+    #     ),
+    # ),
    "deepseek-v3.1-4bit": ModelCard(
        short_id="deepseek-v3.1-4bit",
        model_id=ModelId("mlx-community/DeepSeek-V3.1-4bit"),
@@ -44,6 +70,63 @@ MODEL_CARDS: dict[str, ModelCard] = {
            supports_tensor=True,
        ),
    ),
+    # "deepseek-v3.2": ModelCard(
+    #     short_id="deepseek-v3.2",
+    #     model_id=ModelId("mlx-community/DeepSeek-V3.2-8bit"),
+    #     name="DeepSeek V3.2 (8-bit)",
+    #     description="""DeepSeek V3.2 is a large language model trained on the DeepSeek V3.2 dataset.""",
+    #     tags=[],
+    #     metadata=ModelMetadata(
+    #         model_id=ModelId("mlx-community/DeepSeek-V3.2-8bit"),
+    #         pretty_name="DeepSeek V3.2 (8-bit)",
+    #         storage_size=Memory.from_kb(754706307),
+    #         n_layers=61,
+    #         hidden_size=7168,
+    #     ),
+    # ),
+    # "deepseek-v3.2-4bit": ModelCard(
+    #     short_id="deepseek-v3.2-4bit",
+    #     model_id=ModelId("mlx-community/DeepSeek-V3.2-4bit"),
+    #     name="DeepSeek V3.2 (4-bit)",
+    #     description="""DeepSeek V3.2 is a large language model trained on the DeepSeek V3.2 dataset.""",
+    #     tags=[],
+    #     metadata=ModelMetadata(
+    #         model_id=ModelId("mlx-community/DeepSeek-V3.2-4bit"),
+    #         pretty_name="DeepSeek V3.2 (4-bit)",
+    #         storage_size=Memory.from_kb(754706307 // 2),  # TODO !!!!!
+    #         n_layers=61,
+    #         hidden_size=7168,
+    #     ),
+    # ),
+    # deepseek r1
+    # "deepseek-r1-0528-4bit": ModelCard(
+    #     short_id="deepseek-r1-0528-4bit",
+    #     model_id="mlx-community/DeepSeek-R1-0528-4bit",
+    #     name="DeepSeek-R1-0528 (4-bit)",
+    #     description="""DeepSeek R1 is a large language model trained on the DeepSeek R1 dataset.""",
+    #     tags=[],
+    #     metadata=ModelMetadata(
+    #         model_id=ModelId("mlx-community/DeepSeek-R1-0528-4bit"),
+    #         pretty_name="DeepSeek R1 671B (4-bit)",
+    #         storage_size=Memory.from_kb(409706307),
+    #         n_layers=61,
+    #         hidden_size=7168,
+    #     ),
+    # ),
+    # "deepseek-r1-0528": ModelCard(
+    #     short_id="deepseek-r1-0528",
+    #     model_id="mlx-community/DeepSeek-R1-0528-8bit",
+    #     name="DeepSeek-R1-0528 (8-bit)",
+    #     description="""DeepSeek R1 is a large language model trained on the DeepSeek R1 dataset.""",
+    #     tags=[],
+    #     metadata=ModelMetadata(
+    #         model_id=ModelId("mlx-community/DeepSeek-R1-0528-8bit"),
+    #         pretty_name="DeepSeek R1 671B (8-bit)",
+    #         storage_size=Memory.from_bytes(754998771712),
+    #         n_layers=61,
+    # .       hidden_size=7168,
+    #     ),
+    # ),
    # kimi k2
    "kimi-k2-instruct-4bit": ModelCard(
        short_id="kimi-k2-instruct-4bit",
@@ -425,24 +508,23 @@ MODEL_CARDS: dict[str, ModelCard] = {
            supports_tensor=True,
        ),
    ),
-    "gpt-oss-20b-MXFP4-Q8": ModelCard(
-        short_id="gpt-oss-20b-MXFP4-Q8",
-        model_id=ModelId("mlx-community/gpt-oss-20b-MXFP4-Q8"),
-        name="GPT-OSS 20B (MXFP4-Q8, MLX)",
-        description="""OpenAI's GPT-OSS 20B is a medium-sized MoE model for lower-latency and local or specialized use cases; this variant is a 4-bit MLX conversion for Apple Silicon.""",
+    "gpt-oss-20b-4bit": ModelCard(
+        short_id="gpt-oss-20b-4bit",
+        model_id=ModelId("mlx-community/gpt-oss-20b-MXFP4-Q4"),
+        name="GPT-OSS 20B (MXFP4-Q4, MLX)",
+        description="""OpenAI's GPT-OSS 20B is a medium-sized MoE model for lower-latency and local or specialized use cases; this MLX variant uses MXFP4 4-bit quantization.""",
        tags=[],
        metadata=ModelMetadata(
-            model_id=ModelId("mlx-community/gpt-oss-20b-MXFP4-Q8"),
-            pretty_name="GPT-OSS 20B (MXFP4-Q8, MLX)",
+            model_id=ModelId("mlx-community/gpt-oss-20b-MXFP4-Q4"),
+            pretty_name="GPT-OSS 20B (MXFP4-Q4, MLX)",
            storage_size=Memory.from_kb(11_744_051),
            n_layers=24,
            hidden_size=2880,
            supports_tensor=True,
        ),
    ),
-    # glm 4.5
+    # Needs to be quantized g32 or g16.
    "glm-4.5-air-8bit": ModelCard(
-        # Needs to be quantized g32 or g16 to work with tensor parallel
        short_id="glm-4.5-air-8bit",
        model_id=ModelId("mlx-community/GLM-4.5-Air-8bit"),
        name="GLM 4.5 Air 8bit",
@@ -472,81 +554,19 @@ MODEL_CARDS: dict[str, ModelCard] = {
            supports_tensor=True,
        ),
    ),
-    # glm 4.7
-    "glm-4.7-4bit": ModelCard(
-        short_id="glm-4.7-4bit",
-        model_id=ModelId("mlx-community/GLM-4.7-4bit"),
-        name="GLM 4.7 4bit",
-        description="GLM 4.7 4bit",
-        tags=[],
-        metadata=ModelMetadata(
-            model_id=ModelId("mlx-community/GLM-4.7-4bit"),
-            pretty_name="GLM 4.7 4bit",
-            storage_size=Memory.from_bytes(198556925568),
-            n_layers=91,
-            hidden_size=5120,
-            supports_tensor=True,
-        ),
-    ),
-    "glm-4.7-6bit": ModelCard(
-        short_id="glm-4.7-6bit",
-        model_id=ModelId("mlx-community/GLM-4.7-6bit"),
-        name="GLM 4.7 6bit",
-        description="GLM 4.7 6bit",
-        tags=[],
-        metadata=ModelMetadata(
-            model_id=ModelId("mlx-community/GLM-4.7-6bit"),
-            pretty_name="GLM 4.7 6bit",
-            storage_size=Memory.from_bytes(286737579648),
-            n_layers=91,
-            hidden_size=5120,
-            supports_tensor=True,
-        ),
-    ),
-    "glm-4.7-8bit-gs32": ModelCard(
-        short_id="glm-4.7-8bit-gs32",
-        model_id=ModelId("mlx-community/GLM-4.7-8bit-gs32"),
-        name="GLM 4.7 8bit (gs32)",
-        description="GLM 4.7 8bit (gs32)",
-        tags=[],
-        metadata=ModelMetadata(
-            model_id=ModelId("mlx-community/GLM-4.7-8bit-gs32"),
-            pretty_name="GLM 4.7 8bit (gs32)",
-            storage_size=Memory.from_bytes(396963397248),
-            n_layers=91,
-            hidden_size=5120,
-            supports_tensor=True,
-        ),
-    ),
-    # minimax-m2
-    "minimax-m2.1-8bit": ModelCard(
-        short_id="minimax-m2.1-8bit",
-        model_id=ModelId("mlx-community/MiniMax-M2.1-8bit"),
-        name="MiniMax M2.1 8bit",
-        description="MiniMax M2.1 8bit",
-        tags=[],
-        metadata=ModelMetadata(
-            model_id=ModelId("mlx-community/MiniMax-M2.1-8bit"),
-            pretty_name="MiniMax M2.1 8bit",
-            storage_size=Memory.from_bytes(242986745856),
-            n_layers=61,
-            hidden_size=3072,
-            supports_tensor=True,
-        ),
-    ),
-    "minimax-m2.1-3bit": ModelCard(
-        short_id="minimax-m2.1-3bit",
-        model_id=ModelId("mlx-community/MiniMax-M2.1-3bit"),
-        name="MiniMax M2.1 3bit",
-        description="MiniMax M2.1 3bit",
-        tags=[],
-        metadata=ModelMetadata(
-            model_id=ModelId("mlx-community/MiniMax-M2.1-3bit"),
-            pretty_name="MiniMax M2.1 3bit",
-            storage_size=Memory.from_bytes(100086644736),
-            n_layers=61,
-            hidden_size=3072,
-            supports_tensor=True,
-        ),
-    ),
+    # "devstral-2-123b-instruct-2512-8bit": ModelCard(
+    #     short_id="devstral-2-123b-instruct-2512-8bit",
+    #     model_id=ModelId("mlx-community/Devstral-2-123B-Instruct-2512-8bit"),
+    #     name="Devstral 2 123B Instruct 2512 (8-bit, MLX)",
+    #     description="""Mistral AI's Devstral 2 123B Instruct (2512) is an agentic coding model.""",
+    #     tags=[],
+    #     metadata=ModelMetadata(
+    #         model_id=ModelId("mlx-community/Devstral-2-123B-Instruct-2512-8bit"),
+    #         pretty_name="Devstral 2 123B Instruct 2512 (8-bit, MLX)",
+    #         storage_size=Memory.from_kb(133_000_000),
+    #         n_layers=88,
+    #         hidden_size=12288,
+    #         supports_tensor=True,
+    #     ),
+    # ),
 }
--- a/src/exo/shared/types/api.py
+++ b/src/exo/shared/types/api.py
@@ -11,21 +11,10 @@ from exo.shared.types.worker.instances import Instance, InstanceId, InstanceMeta
 from exo.shared.types.worker.shards import Sharding

 FinishReason = Literal[
-    "stop", "length", "tool_calls", "content_filter", "function_call", "error"
+    "stop", "length", "tool_calls", "content_filter", "function_call"
 ]


-class ErrorInfo(BaseModel):
-    message: str
-    type: str
-    param: str | None = None
-    code: int
-
-
-class ErrorResponse(BaseModel):
-    error: ErrorInfo
-
-
 class ModelListModel(BaseModel):
    id: str
    object: str = "model"
@@ -161,8 +150,6 @@ class ChatCompletionTaskParams(BaseModel):
    tool_choice: str | dict[str, Any] | None = None
    parallel_tool_calls: bool | None = None
    user: str | None = None
-    # Speculative decoding: tokens to draft per iteration (if instance has draft model)
-    num_draft_tokens: int = 3


 class BenchChatCompletionTaskParams(ChatCompletionTaskParams):
@@ -174,8 +161,6 @@ class PlaceInstanceParams(BaseModel):
    sharding: Sharding = Sharding.Pipeline
    instance_meta: InstanceMeta = InstanceMeta.MlxRing
    min_nodes: int = 1
-    draft_model: ModelId | None = None  # For speculative decoding
-    num_draft_tokens: int = 4  # Tokens to draft per iteration

    @field_validator("sharding", "instance_meta", mode="plain")
    @classmethod
--- a/src/exo/shared/types/chunks.py
+++ b/src/exo/shared/types/chunks.py
@@ -22,7 +22,6 @@ class TokenChunk(BaseChunk):
    token_id: int
    finish_reason: FinishReason | None = None
    stats: GenerationStats | None = None
-    error_message: str | None = None


 class ImageChunk(BaseChunk):
--- a/src/exo/shared/types/commands.py
+++ b/src/exo/shared/types/commands.py
@@ -2,7 +2,7 @@ from pydantic import Field

 from exo.shared.types.api import ChatCompletionTaskParams
 from exo.shared.types.common import CommandId, NodeId
-from exo.shared.types.models import ModelId, ModelMetadata
+from exo.shared.types.models import ModelMetadata
 from exo.shared.types.worker.instances import Instance, InstanceId, InstanceMeta
 from exo.shared.types.worker.shards import Sharding
 from exo.utils.pydantic_ext import CamelCaseModel, TaggedModel
@@ -25,8 +25,6 @@ class PlaceInstance(BaseCommand):
    sharding: Sharding
    instance_meta: InstanceMeta
    min_nodes: int
-    draft_model: ModelId | None = None  # For speculative decoding
-    num_draft_tokens: int = 4  # Tokens to draft per iteration


 class CreateInstance(BaseCommand):
--- a/src/exo/shared/types/worker/instances.py
+++ b/src/exo/shared/types/worker/instances.py
@@ -3,7 +3,6 @@ from enum import Enum
 from pydantic import model_validator

 from exo.shared.types.common import Host, Id, NodeId
-from exo.shared.types.models import ModelId
 from exo.shared.types.worker.runners import RunnerId, ShardAssignments, ShardMetadata
 from exo.utils.pydantic_ext import CamelCaseModel, TaggedModel

@@ -20,8 +19,6 @@ class InstanceMeta(str, Enum):
 class BaseInstance(TaggedModel):
    instance_id: InstanceId
    shard_assignments: ShardAssignments
-    draft_model: ModelId | None = None  # For speculative decoding (rank 0 only)
-    num_draft_tokens: int = 4  # Tokens to draft per iteration (when draft_model is set)

    def shard(self, runner_id: RunnerId) -> ShardMetadata | None:
        return self.shard_assignments.runner_to_shard.get(runner_id, None)
--- a/src/exo/worker/engines/mlx/auto_parallel.py
+++ b/src/exo/worker/engines/mlx/auto_parallel.py
@@ -10,24 +10,18 @@ from mlx.nn.layers.distributed import (
    shard_linear,
    sum_gradients,
 )
+from mlx_lm.models.cache import (
+    _BaseCache,  # pyright: ignore[reportPrivateUsage]
+)
 from mlx_lm.models.deepseek_v3 import DeepseekV3MLP
 from mlx_lm.models.deepseek_v3 import Model as DeepseekV3Model
-from mlx_lm.models.deepseek_v32 import DeepseekV32MLP
-from mlx_lm.models.deepseek_v32 import Model as DeepseekV32Model
-from mlx_lm.models.glm4_moe import Model as Glm4MoeModel
-from mlx_lm.models.glm4_moe import MoE
-from mlx_lm.models.gpt_oss import GptOssMoeModel
-from mlx_lm.models.gpt_oss import Model as GptOssModel
 from mlx_lm.models.llama import Model as LlamaModel
-from mlx_lm.models.minimax import Model as MiniMaxModel
-from mlx_lm.models.ministral3 import Model as Ministral3Model
 from mlx_lm.models.qwen3_moe import Model as Qwen3MoeModel
 from mlx_lm.models.qwen3_moe import Qwen3MoeSparseMoeBlock
-from mlx_lm.models.qwen3_next import Model as Qwen3NextModel
-from mlx_lm.models.qwen3_next import Qwen3NextSparseMoeBlock

-from exo.shared.logging import logger
-from exo.shared.types.worker.shards import PipelineShardMetadata
+from exo.shared.types.worker.shards import (
+    PipelineShardMetadata,
+)


 class _LayerCallable(Protocol):
@@ -97,6 +91,8 @@ class PipelineLastLayer(CustomMlxLayer):
            x, *args, **kwargs
        ).arguments.get("cache", None)

+        assert cache is None or issubclass(type(cache), _BaseCache)  # type: ignore
+
        output: mx.array = self.original_layer(x, *args, **kwargs)

        if self.r != self.s - 1:
@@ -104,6 +100,7 @@ class PipelineLastLayer(CustomMlxLayer):
                output, (self.r + 1) % self.s, group=self.group
            )
            if cache is not None:
+                # This change happened upstream - check out mlx github somewhere??
                cache.keys = mx.depends(cache.keys, output)  # type: ignore[reportUnknownMemberType]

        output = mx.distributed.all_gather(output, group=self.group)[-output.shape[0] :]
@@ -135,6 +132,24 @@ def _get_layers(inner_model_instance: nn.Module) -> list[_LayerCallable]:
    return layers


+def _set_layers(model: nn.Module, layers: list[_LayerCallable]) -> None:
+    inner_model_instance = _inner_model(model)
+    if hasattr(inner_model_instance, "layers"):
+        inner_model_instance.layers = layers
+
+        # Update DeepSeek V3 specific parameters when layers are shrunk
+        if isinstance(model, DeepseekV3Model) and hasattr(
+            inner_model_instance, "num_layers"
+        ):
+            inner_model_instance.start_idx = 0
+            inner_model_instance.end_idx = len(layers)
+            inner_model_instance.num_layers = len(layers)
+    elif hasattr(inner_model_instance, "h"):
+        inner_model_instance.h = layers
+    else:
+        raise ValueError("Model must have either a 'layers' or 'h' attribute")
+
+
 def pipeline_auto_parallel(
    model: nn.Module,
    group: mx.distributed.Group,
@@ -150,7 +165,8 @@ def pipeline_auto_parallel(
    """
    inner_model_instance: nn.Module = _inner_model(model)

-    layers = _get_layers(inner_model_instance)
+    # Handle both model.layers and model.h cases
+    layers: list[_LayerCallable] = _get_layers(inner_model_instance)

    start_layer, end_layer = model_shard_meta.start_layer, model_shard_meta.end_layer
    device_rank, world_size = model_shard_meta.device_rank, model_shard_meta.world_size
@@ -164,17 +180,6 @@ def pipeline_auto_parallel(
        group=group,
    )

-    if isinstance(inner_model_instance, GptOssMoeModel):
-        inner_model_instance.layer_types = inner_model_instance.layer_types[  # type: ignore
-            start_layer:end_layer
-        ]
-        inner_model_instance.swa_idx = inner_model_instance.layer_types.index(  # type: ignore
-            "sliding_attention"
-        )
-        inner_model_instance.ga_idx = inner_model_instance.layer_types.index(  # type: ignore
-            "full_attention"
-        )
-
    _set_layers(model, layers)

    assert isinstance(layers, list), (
@@ -199,44 +204,18 @@ def tensor_auto_parallel(
        group=group,
    )

-    segments: int = 1
-
-    def _all_to_sharded(path: str, weight: mx.array):
-        if path.endswith("bias"):
-            logger.info(f"Sharding bias for {path} - all to sharded")
-            return weight.ndim - 1, segments
-        return max(weight.ndim - 2, 0), segments
-
    all_to_sharded_linear_in_place = partial(
        shard_inplace,
-        sharding=_all_to_sharded,  # type: ignore
+        sharding="all-to-sharded",
        group=group,
    )
-
-    n = group.size()
-
-    def _sharded_to_all(path: str, weight: mx.array):
-        if path.endswith("bias"):
-            logger.info(f"Sharding bias for {path} - sharded to all")
-            weight /= n
-            return None
-        return -1, segments
-
    sharded_to_all_linear_in_place = partial(
        shard_inplace,
-        sharding=_sharded_to_all,  # type: ignore
+        sharding="sharded-to-all",
        group=group,
    )

-    if hasattr(model, "shard"):
-        try:
-            model.shard(group)  # type: ignore
-            return model
-        except (AttributeError, TypeError, NameError):
-            pass
-
-    if isinstance(model, (LlamaModel, Ministral3Model)):
-        logger.warning("shouldn't be hit - upstream sharding exists")
+    if isinstance(model, LlamaModel):
        tensor_parallel_sharding_strategy = LlamaShardingStrategy(
            group,
            all_to_sharded_linear,
@@ -244,8 +223,7 @@ def tensor_auto_parallel(
            all_to_sharded_linear_in_place,
            sharded_to_all_linear_in_place,
        )
-    elif isinstance(model, (DeepseekV3Model, DeepseekV32Model)):
-        logger.warning("shouldn't be hit - upstream sharding exists")
+    elif isinstance(model, DeepseekV3Model):
        tensor_parallel_sharding_strategy = DeepSeekShardingStrategy(
            group,
            all_to_sharded_linear,
@@ -253,15 +231,7 @@ def tensor_auto_parallel(
            all_to_sharded_linear_in_place,
            sharded_to_all_linear_in_place,
        )
-    elif isinstance(model, MiniMaxModel):
-        tensor_parallel_sharding_strategy = MiniMaxShardingStrategy(
-            group,
-            all_to_sharded_linear,
-            sharded_to_all_linear,
-            all_to_sharded_linear_in_place,
-            sharded_to_all_linear_in_place,
-        )
-    elif isinstance(model, (Qwen3MoeModel, Glm4MoeModel, Qwen3NextModel)):
+    elif isinstance(model, Qwen3MoeModel):
        tensor_parallel_sharding_strategy = QwenShardingStrategy(
            group,
            all_to_sharded_linear,
@@ -269,15 +239,6 @@ def tensor_auto_parallel(
            all_to_sharded_linear_in_place,
            sharded_to_all_linear_in_place,
        )
-    elif isinstance(model, GptOssModel):
-        tensor_parallel_sharding_strategy = GptOssShardingStrategy(
-            group,
-            all_to_sharded_linear,
-            sharded_to_all_linear,
-            all_to_sharded_linear_in_place,
-            sharded_to_all_linear_in_place,
-        )
-
    else:
        raise ValueError(f"Unsupported model type: {type(model)}")

@@ -323,32 +284,6 @@ class LlamaShardingStrategy(TensorParallelShardingStrategy):
        return model


-def _set_layers(model: nn.Module, layers: list[_LayerCallable]) -> None:
-    inner_model_instance = _inner_model(model)
-    if hasattr(inner_model_instance, "layers"):
-        inner_model_instance.layers = layers
-
-        # Update DeepSeek V3 specific parameters when layers are shrunk
-        if isinstance(
-            model, (DeepseekV3Model, DeepseekV32Model, Glm4MoeModel)
-        ) and hasattr(inner_model_instance, "num_layers"):
-            logger.info(
-                f"Setting num_layers to {len(layers)} for model {model.model.__class__.__name__}"
-            )
-            inner_model_instance.start_idx = 0
-            inner_model_instance.end_idx = len(layers)
-            inner_model_instance.num_layers = len(layers)
-        elif isinstance(model, Qwen3MoeModel):
-            logger.info(
-                f"Setting num_hidden_layers to {len(layers)} for model {model.model.__class__.__name__}"
-            )
-            inner_model_instance.num_hidden_layers = len(layers)
-    elif hasattr(inner_model_instance, "h"):
-        inner_model_instance.h = layers
-    else:
-        raise ValueError("Model must have either a 'layers' or 'h' attribute")
-
-
 class DeepSeekShardingStrategy(TensorParallelShardingStrategy):
    def shard_model(self, model: nn.Module) -> nn.Module:
        model = cast(DeepseekV3Model, model)
@@ -369,7 +304,7 @@ class DeepSeekShardingStrategy(TensorParallelShardingStrategy):
            layer.self_attn.num_heads //= self.N

            # Shard the MLP
-            if isinstance(layer.mlp, (DeepseekV3MLP, DeepseekV32MLP)):
+            if isinstance(layer.mlp, DeepseekV3MLP):
                layer.mlp.gate_proj = self.all_to_sharded_linear(layer.mlp.gate_proj)
                layer.mlp.down_proj = self.sharded_to_all_linear(layer.mlp.down_proj)
                layer.mlp.up_proj = self.all_to_sharded_linear(layer.mlp.up_proj)
@@ -403,35 +338,6 @@ class ShardedDeepseekV3MoE(CustomMlxLayer):
        return y


-class MiniMaxShardingStrategy(TensorParallelShardingStrategy):
-    def shard_model(self, model: nn.Module) -> nn.Module:
-        model = cast(MiniMaxModel, model)
-        for layer in model.layers:
-            # Shard the self attention
-            layer.self_attn.q_proj = self.all_to_sharded_linear(layer.self_attn.q_proj)
-            layer.self_attn.k_proj = self.all_to_sharded_linear(layer.self_attn.k_proj)
-            layer.self_attn.v_proj = self.all_to_sharded_linear(layer.self_attn.v_proj)
-            layer.self_attn.o_proj = self.sharded_to_all_linear(layer.self_attn.o_proj)
-            layer.self_attn.num_attention_heads //= self.N
-            layer.self_attn.num_key_value_heads //= self.N
-
-            # Shard the MoE. Shard in place since the MoE should be responsible
-            # for aggregating the results.
-            self.all_to_sharded_linear_in_place(
-                layer.block_sparse_moe.switch_mlp.gate_proj
-            )
-            self.sharded_to_all_linear_in_place(
-                layer.block_sparse_moe.switch_mlp.down_proj
-            )
-            self.all_to_sharded_linear_in_place(
-                layer.block_sparse_moe.switch_mlp.up_proj
-            )
-            layer.block_sparse_moe = ShardedQwenMoE(layer.block_sparse_moe)  # pyright: ignore[reportAttributeAccessIssue, reportArgumentType]
-            layer.block_sparse_moe.sharding_group = self.group
-
-        return model
-
-
 class QwenShardingStrategy(TensorParallelShardingStrategy):
    def shard_model(self, model: nn.Module) -> nn.Module:
        model = cast(Qwen3MoeModel, model)
@@ -446,13 +352,11 @@ class QwenShardingStrategy(TensorParallelShardingStrategy):

            # Shard the MoE. Shard in place since the MoE should be responsible
            # for aggregating the results.
-            if isinstance(
-                layer.mlp, (Qwen3MoeSparseMoeBlock, MoE, Qwen3NextSparseMoeBlock)
-            ):
+            if isinstance(layer.mlp, Qwen3MoeSparseMoeBlock):
                self.all_to_sharded_linear_in_place(layer.mlp.switch_mlp.gate_proj)
                self.sharded_to_all_linear_in_place(layer.mlp.switch_mlp.down_proj)
                self.all_to_sharded_linear_in_place(layer.mlp.switch_mlp.up_proj)
-                layer.mlp = ShardedQwenMoE(layer.mlp)  # pyright: ignore[reportAttributeAccessIssue, reportArgumentType]
+                layer.mlp = ShardedQwenMoE(layer.mlp)  # type: ignore
                layer.mlp.sharding_group = self.group

            # Shard the MLP
@@ -476,50 +380,3 @@ class ShardedQwenMoE(CustomMlxLayer):
        if self.sharding_group is not None:
            y = mx.distributed.all_sum(y, group=self.sharding_group)
        return y
-
-
-class GptOssShardingStrategy(TensorParallelShardingStrategy):
-    def shard_model(self, model: nn.Module) -> nn.Module:
-        model = cast(GptOssMoeModel, model)
-
-        for layer in model.layers:
-            layer.self_attn.q_proj = self.all_to_sharded_linear(layer.self_attn.q_proj)
-            layer.self_attn.k_proj = self.all_to_sharded_linear(layer.self_attn.k_proj)
-            layer.self_attn.v_proj = self.all_to_sharded_linear(layer.self_attn.v_proj)
-            layer.self_attn.o_proj = self.sharded_to_all_linear(layer.self_attn.o_proj)
-
-            layer.self_attn.num_attention_heads //= self.N
-            layer.self_attn.num_key_value_heads //= self.N
-            layer.self_attn.num_key_value_groups = (
-                layer.self_attn.num_attention_heads
-                // layer.self_attn.num_key_value_heads
-            )
-
-            layer.self_attn.sinks = layer.self_attn.sinks[
-                layer.self_attn.num_attention_heads
-                * self.group.rank() : layer.self_attn.num_attention_heads
-                * (self.group.rank() + 1)
-            ]
-
-            self.all_to_sharded_linear_in_place(layer.mlp.experts.gate_proj)
-            self.sharded_to_all_linear_in_place(layer.mlp.experts.down_proj)
-            self.all_to_sharded_linear_in_place(layer.mlp.experts.up_proj)
-
-            layer.mlp = ShardedGptOssMoE(layer.mlp)  # type: ignore
-            layer.mlp.sharding_group = self.group
-
-        return model
-
-
-class ShardedGptOssMoE(CustomMlxLayer):
-    def __init__(self, layer: nn.Module):
-        super().__init__(layer)
-        self.sharding_group: mx.distributed.Group | None = None
-
-    def __call__(self, x: mx.array) -> mx.array:
-        if self.sharding_group is not None:
-            x = sum_gradients(self.sharding_group)(x)
-        y = self.original_layer(x)
-        if self.sharding_group is not None:
-            y = mx.distributed.all_sum(y, group=self.sharding_group)
-        return y
--- a/src/exo/worker/engines/mlx/generator/generate.py
+++ b/src/exo/worker/engines/mlx/generator/generate.py
@@ -119,8 +119,6 @@ def mlx_generate(
    model: Model,
    tokenizer: TokenizerWrapper,
    task: ChatCompletionTaskParams,
-    draft_model: Model | None = None,
-    num_draft_tokens: int = 4,
 ) -> Generator[GenerationResponse]:
    # Ensure that generation stats only contains peak memory for this generation
    mx.reset_peak_memory()
@@ -137,6 +135,8 @@ def mlx_generate(
        chat_task_data=task,
    )

+    caches = make_kv_cache(model=model)
+
    logits_processors: list[Callable[[mx.array, mx.array], mx.array]] = []
    if is_bench:
        # Only sample length eos tokens
@@ -149,31 +149,19 @@ def mlx_generate(
    )

    max_tokens = task.max_tokens or MAX_TOKENS
-
-    # Build kwargs for stream_generate, conditionally adding draft model params
-    generate_kwargs: dict[str, object] = {
-        "model": model,
-        "tokenizer": tokenizer,
-        "prompt": prompt,
-        "max_tokens": max_tokens,
-        "sampler": sampler,
-        "logits_processors": logits_processors,
-        "prefill_step_size": 2048,
-        "kv_group_size": KV_GROUP_SIZE,
-        "kv_bits": KV_BITS,
-    }
-
-    # Add speculative decoding parameters if draft model is provided
-    # Note: When using draft_model, we let mlx_lm create its own trimmable cache
-    # as speculative decoding requires cache trimming capabilities
-    if draft_model is not None:
-        generate_kwargs["draft_model"] = draft_model
-        generate_kwargs["num_draft_tokens"] = num_draft_tokens
-    else:
-        # Only use custom cache for non-speculative generation
-        generate_kwargs["prompt_cache"] = make_kv_cache(model=model)
-
-    for out in stream_generate(**generate_kwargs):  # type: ignore[arg-type]
+    for out in stream_generate(
+        model=model,
+        tokenizer=tokenizer,
+        prompt=prompt,
+        max_tokens=max_tokens,
+        sampler=sampler,
+        logits_processors=logits_processors,
+        prompt_cache=caches,
+        # TODO: Dynamically change prefill step size to be the maximum possible without timing out.
+        prefill_step_size=2048,
+        kv_group_size=KV_GROUP_SIZE,
+        kv_bits=KV_BITS,
+    ):
        logger.info(out.text)

        stats: GenerationStats | None = None
--- a/src/exo/worker/engines/mlx/utils_mlx.py
+++ b/src/exo/worker/engines/mlx/utils_mlx.py
@@ -2,9 +2,7 @@ import json
 import os
 import resource
 import sys
-import threading
 import time
-from collections.abc import Callable
 from pathlib import Path
 from typing import Any, cast

@@ -22,7 +20,6 @@ except ImportError:

 from mlx_lm.models.cache import KVCache, QuantizedKVCache, RotatingKVCache
 from mlx_lm.models.deepseek_v3 import DeepseekV3Model
-from mlx_lm.models.gpt_oss import Model as GptOssModel
 from mlx_lm.tokenizer_utils import TokenizerWrapper

 from exo.worker.engines.mlx.constants import (
@@ -84,45 +81,6 @@ def get_weights_size(model_shard_meta: ShardMetadata) -> Memory:
    )


-class ModelLoadingTimeoutError(Exception):
-    pass
-
-
-TimeoutCallback = Callable[[], None]
-
-
-def eval_with_timeout(
-    mlx_item: Any,  # pyright: ignore[reportAny]
-    timeout_seconds: float = 60.0,
-    on_timeout: TimeoutCallback | None = None,
-) -> None:
-    """Evaluate MLX item with a hard timeout.
-
-    If on_timeout callback is provided, it will be called before terminating
-    the process. This allows the runner to send a failure event before exit.
-    """
-    completed = threading.Event()
-
-    def watchdog() -> None:
-        if not completed.wait(timeout=timeout_seconds):
-            logger.error(
-                f"mlx_item evaluation timed out after {timeout_seconds:.0f}s. "
-                "This may indicate an issue with FAST_SYNCH and tensor parallel sharding. "
-                "Terminating process."
-            )
-            if on_timeout is not None:
-                on_timeout()
-            os._exit(1)
-
-    watchdog_thread = threading.Thread(target=watchdog, daemon=True)
-    watchdog_thread.start()
-
-    try:
-        mx.eval(mlx_item)  # pyright: ignore[reportAny]
-    finally:
-        completed.set()
-
-
 def mx_barrier(group: Group | None = None):
    mx.eval(
        mx.distributed.all_sum(
@@ -229,9 +187,7 @@ def initialize_mlx(


 def load_mlx_items(
-    bound_instance: BoundInstance,
-    group: Group | None,
-    on_timeout: TimeoutCallback | None = None,
+    bound_instance: BoundInstance, group: Group | None
 ) -> tuple[Model, TokenizerWrapper]:
    if group is None:
        logger.info(f"Single device used for {bound_instance.instance}")
@@ -245,9 +201,7 @@ def load_mlx_items(
    else:
        logger.info("Starting distributed init")
        start_time = time.perf_counter()
-        model, tokenizer = shard_and_load(
-            bound_instance.bound_shard, group=group, on_timeout=on_timeout
-        )
+        model, tokenizer = shard_and_load(bound_instance.bound_shard, group=group)
        end_time = time.perf_counter()
        logger.info(
            f"Time taken to shard and load model: {(end_time - start_time):.2f}s"
@@ -258,31 +212,9 @@ def load_mlx_items(
    return cast(Model, model), tokenizer


-def load_draft_model(model_id: str) -> nn.Module:
-    """Load a draft model for speculative decoding (rank 0 only).
-
-    Draft models are small models (typically 0.5B-2B parameters) used to
-    generate candidate tokens quickly, which are then verified by the main
-    model in a single forward pass.
-
-    Assumes the model has already been downloaded by the worker.
-
-    Args:
-        model_id: HuggingFace model ID for the draft model
-
-    Returns:
-        The loaded draft model
-    """
-    model_path = build_model_path(model_id)
-    draft_model, _ = load_model(model_path, strict=True)
-    logger.info(f"Loaded draft model from {model_path}")
-    return draft_model
-
-
 def shard_and_load(
    shard_metadata: ShardMetadata,
    group: Group,
-    on_timeout: TimeoutCallback | None = None,
 ) -> tuple[nn.Module, TokenizerWrapper]:
    model_path = build_model_path(shard_metadata.model_meta.model_id)

@@ -319,15 +251,7 @@ def shard_and_load(
            logger.info(f"loading model from {model_path} with pipeline parallelism")
            model = pipeline_auto_parallel(model, group, shard_metadata)

-    # Estimate timeout based on model size
-    base_timeout = float(os.environ.get("EXO_MODEL_LOAD_TIMEOUT", "60"))
-    model_size_gb = get_weights_size(shard_metadata).in_bytes / (1024**3)
-    timeout_seconds = base_timeout + model_size_gb / 5
-    logger.info(
-        f"Evaluating model parameters with timeout of {timeout_seconds:.0f}s "
-        f"(model size: {model_size_gb:.1f}GB)"
-    )
-    eval_with_timeout(model.parameters(), timeout_seconds, on_timeout)
+    mx.eval(model.parameters())

    # TODO: Do we need this?
    mx.eval(model)
@@ -441,8 +365,6 @@ def apply_chat_template(
        tools=chat_task_data.tools,
    )

-    logger.info(prompt)
-
    return prompt


@@ -474,11 +396,6 @@ def make_kv_cache(
 ) -> list[KVCache | RotatingKVCache | QuantizedKVCache]:
    assert hasattr(model, "layers")

-    # TODO: Do this for all models
-    if hasattr(model, "make_cache") and isinstance(model, GptOssModel):
-        logger.info("Using MLX LM's make cache")
-        return model.make_cache()  # type: ignore
-
    if max_kv_size is None:
        if KV_CACHE_BITS is None:
            logger.info("Using default KV cache")
--- a/src/exo/worker/plan.py
+++ b/src/exo/worker/plan.py
@@ -3,8 +3,7 @@
 from collections.abc import Mapping, Sequence

 from exo.shared.types.common import NodeId
-from exo.shared.types.memory import Memory
-from exo.shared.types.models import ModelId, ModelMetadata
+from exo.shared.types.models import ModelId
 from exo.shared.types.tasks import (
    ChatCompletion,
    ConnectToGroup,
@@ -36,7 +35,6 @@ from exo.shared.types.worker.runners import (
    RunnerStatus,
    RunnerWarmingUp,
 )
-from exo.shared.types.worker.shards import PipelineShardMetadata
 from exo.worker.runner.runner_supervisor import RunnerSupervisor


@@ -59,7 +57,6 @@ def plan(
        or _model_needs_download(runners, download_status)
        or _init_distributed_backend(runners, all_runners)
        or _load_model(runners, all_runners, global_download_status)
-        or _draft_model_needs_download(runners, download_status)
        or _ready_to_warmup(runners, all_runners)
        or _pending_tasks(runners, tasks, all_runners)
    )
@@ -131,57 +128,6 @@ def _model_needs_download(
            )


-def _draft_model_needs_download(
-    runners: Mapping[RunnerId, RunnerSupervisor],
-    download_status: Mapping[ModelId, DownloadProgress],
-) -> DownloadModel | None:
-    """Check if draft model needs download (for speculative decoding).
-
-    Only rank 0 needs the draft model, and only after the main model is loaded.
-    """
-    for runner in runners.values():
-        instance = runner.bound_instance.instance
-        shard = runner.bound_instance.bound_shard
-
-        # Only check when runner is loaded and ready for warmup
-        if not isinstance(runner.status, RunnerLoaded):
-            continue
-
-        # Only rank 0 loads the draft model
-        if shard.device_rank != 0:
-            continue
-
-        # Check if instance has a draft model configured
-        draft_model_id = instance.draft_model
-        if draft_model_id is None:
-            continue
-
-        # Check if draft model needs download
-        if draft_model_id not in download_status or not isinstance(
-            download_status[draft_model_id], (DownloadOngoing, DownloadCompleted)
-        ):
-            # Create minimal shard metadata for draft model download
-            draft_shard = PipelineShardMetadata(
-                model_meta=ModelMetadata(
-                    model_id=draft_model_id,
-                    pretty_name=str(draft_model_id),
-                    storage_size=Memory.from_bytes(0),  # Unknown, will be determined during download
-                    n_layers=1,  # Placeholder
-                    hidden_size=1,  # Placeholder
-                    supports_tensor=False,
-                ),
-                device_rank=0,
-                world_size=1,
-                start_layer=0,
-                end_layer=1,
-                n_layers=1,
-            )
-            return DownloadModel(
-                instance_id=instance.instance_id,
-                shard_metadata=draft_shard,
-            )
-
-
 def _init_distributed_backend(
    runners: Mapping[RunnerId, RunnerSupervisor],
    all_runners: Mapping[RunnerId, RunnerStatus],
--- a/src/exo/worker/runner/bootstrap.py
+++ b/src/exo/worker/runner/bootstrap.py
@@ -17,23 +17,15 @@ def entrypoint(
    task_receiver: MpReceiver[Task],
    _logger: "loguru.Logger",
 ) -> None:
-    fast_synch_override = os.environ.get("EXO_FAST_SYNCH")
-    if fast_synch_override == "on" or (
-        fast_synch_override != "off"
-        and (
-            isinstance(bound_instance.instance, MlxJacclInstance)
-            and len(bound_instance.instance.ibv_devices) >= 2
-        )
+    if (
+        isinstance(bound_instance.instance, MlxJacclInstance)
+        and len(bound_instance.instance.ibv_devices) >= 2
    ):
        os.environ["MLX_METAL_FAST_SYNCH"] = "1"
-    else:
-        os.environ["MLX_METAL_FAST_SYNCH"] = "0"

    global logger
    logger = _logger

-    logger.info(f"Fast synch flag: {os.environ['MLX_METAL_FAST_SYNCH']}")
-
    # Import main after setting global logger - this lets us just import logger from this module
    try:
        from exo.worker.runner.runner import main
--- a/src/exo/worker/runner/runner.py
+++ b/src/exo/worker/runner/runner.py
@@ -1,21 +1,9 @@
 import time
-from collections.abc import Generator
-from contextlib import contextmanager
-from functools import cache
-from typing import cast

 import mlx.core as mx
-from mlx_lm.models.gpt_oss import Model as GptOssModel
-from openai_harmony import (  # pyright: ignore[reportMissingTypeStubs]
-    HarmonyEncodingName,
-    Role,
-    StreamableParser,
-    load_harmony_encoding,
-)

 from exo.shared.types.api import ChatCompletionMessageText
 from exo.shared.types.chunks import TokenChunk
-from exo.shared.types.common import CommandId
 from exo.shared.types.events import (
    ChunkGenerated,
    Event,
@@ -23,7 +11,6 @@ from exo.shared.types.events import (
    TaskAcknowledged,
    TaskStatusUpdated,
 )
-from exo.shared.types.models import ModelId
 from exo.shared.types.tasks import (
    ChatCompletion,
    ConnectToGroup,
@@ -52,44 +39,15 @@ from exo.shared.types.worker.runners import (
    RunnerWarmingUp,
 )
 from exo.utils.channels import MpReceiver, MpSender
-from exo.worker.engines.mlx import Model
 from exo.worker.engines.mlx.generator.generate import mlx_generate, warmup_inference
 from exo.worker.engines.mlx.utils_mlx import (
    initialize_mlx,
-    load_draft_model,
    load_mlx_items,
    mlx_force_oom,
 )
 from exo.worker.runner.bootstrap import logger


-@contextmanager
-def send_error_chunk_on_exception(
-    event_sender: MpSender[Event],
-    command_id: CommandId,
-    model_id: ModelId,
-    device_rank: int,
-):
-    try:
-        yield
-    except Exception as e:
-        logger.error(e)
-        if device_rank == 0:
-            event_sender.send(
-                ChunkGenerated(
-                    command_id=command_id,
-                    chunk=TokenChunk(
-                        idx=0,
-                        model=model_id,
-                        text="",
-                        token_id=0,
-                        finish_reason="error",
-                        error_message=str(e),
-                    ),
-                )
-            )
-
-
 def main(
    bound_instance: BoundInstance,
    event_sender: MpSender[Event],
@@ -111,7 +69,6 @@ def main(
    model = None
    tokenizer = None
    group = None
-    draft_model: Model | None = None  # Loaded during warmup if instance has draft_model

    current_status: RunnerStatus = RunnerIdle()
    logger.info("runner created")
@@ -152,20 +109,7 @@ def main(
                        )
                    )

-                    def on_model_load_timeout() -> None:
-                        event_sender.send(
-                            RunnerStatusUpdated(
-                                runner_id=runner_id,
-                                runner_status=RunnerFailed(
-                                    error_message="Model loading timed out"
-                                ),
-                            )
-                        )
-                        time.sleep(0.5)
-
-                    model, tokenizer = load_mlx_items(
-                        bound_instance, group, on_timeout=on_model_load_timeout
-                    )
+                    model, tokenizer = load_mlx_items(bound_instance, group)

                    current_status = RunnerLoaded()
                    logger.info("runner loaded")
@@ -180,20 +124,11 @@ def main(
                        )
                    )

-                    # Load draft model for speculative decoding (rank 0 only)
-                    if (
-                        instance.draft_model is not None
-                        and shard_metadata.device_rank == 0
-                    ):
-                        logger.info(f"Loading draft model: {instance.draft_model}")
-                        draft_model = cast(
-                            Model, load_draft_model(str(instance.draft_model))
-                        )
-
                    logger.info(f"warming up inference for instance: {instance}")
                    toks = warmup_inference(
-                        model=cast(Model, model),
+                        model=model,
                        tokenizer=tokenizer,
+                        # kv_prefix_cache=kv_prefix_cache,  # supply for warmup-time prefix caching
                    )
                    logger.info(f"warmed up by generating {toks} tokens")
                    logger.info(
@@ -204,6 +139,8 @@ def main(
                case ChatCompletion(task_params=task_params, command_id=command_id) if (
                    isinstance(current_status, RunnerReady)
                ):
+                    assert model
+                    assert tokenizer
                    logger.info(f"received chat request: {str(task)[:500]}")
                    current_status = RunnerRunning()
                    logger.info("runner running")
@@ -212,49 +149,33 @@ def main(
                            runner_id=runner_id, runner_status=current_status
                        )
                    )
-                    with send_error_chunk_on_exception(
-                        event_sender,
-                        command_id,
-                        shard_metadata.model_meta.model_id,
-                        shard_metadata.device_rank,
+                    assert task_params.messages[0].content is not None
+                    _check_for_debug_prompts(task_params.messages[0].content)
+
+                    # Generate responses using the actual MLX generation
+                    for response in mlx_generate(
+                        model=model,
+                        tokenizer=tokenizer,
+                        task=task_params,
                    ):
-                        assert model
-                        assert tokenizer
-                        assert task_params.messages[0].content is not None
-                        _check_for_debug_prompts(task_params.messages[0].content)
-
-                        # Generate responses (draft_model loaded at warmup if configured)
-                        mlx_generator = mlx_generate(
-                            model=cast(Model, model),
-                            tokenizer=tokenizer,
-                            task=task_params,
-                            draft_model=draft_model,
-                            num_draft_tokens=instance.num_draft_tokens,
-                        )
-
-                        # GPT-OSS specific parsing to match other model formats.
-                        if isinstance(model, GptOssModel):
-                            mlx_generator = parse_gpt_oss(mlx_generator)
-
-                        # TODO: Add tool call parser here
-
-                        for response in mlx_generator:
-                            match response:
-                                case GenerationResponse():
-                                    if shard_metadata.device_rank == 0:
-                                        event_sender.send(
-                                            ChunkGenerated(
-                                                command_id=command_id,
-                                                chunk=TokenChunk(
-                                                    idx=response.token,
-                                                    model=shard_metadata.model_meta.model_id,
-                                                    text=response.text,
-                                                    token_id=response.token,
-                                                    finish_reason=response.finish_reason,
-                                                    stats=response.stats,
-                                                ),
-                                            )
+                        match response:
+                            case GenerationResponse():
+                                if shard_metadata.device_rank == 0:
+                                    event_sender.send(
+                                        ChunkGenerated(
+                                            command_id=command_id,
+                                            chunk=TokenChunk(
+                                                idx=response.token,
+                                                model=shard_metadata.model_meta.model_id,
+                                                text=response.text,
+                                                token_id=response.token,
+                                                finish_reason=response.finish_reason,
+                                                stats=response.stats,
+                                            ),
                                        )
+                                    )
+                                # case TokenizedResponse():
+                                # TODO: something here ig

                    current_status = RunnerReady()
                    logger.info("runner ready")
@@ -278,7 +199,7 @@ def main(
                RunnerStatusUpdated(runner_id=runner_id, runner_status=current_status)
            )
            if isinstance(current_status, RunnerShutdown):
-                del model, tokenizer, group, draft_model
+                del model, tokenizer, group
                mx.clear_cache()
                import gc

@@ -286,43 +207,6 @@ def main(
                break


-@cache
-def get_gpt_oss_encoding():
-    encoding = load_harmony_encoding(HarmonyEncodingName.HARMONY_GPT_OSS)
-    return encoding
-
-
-def parse_gpt_oss(
-    responses: Generator[GenerationResponse],
-) -> Generator[GenerationResponse]:
-    encoding = get_gpt_oss_encoding()
-    stream = StreamableParser(encoding, role=Role.ASSISTANT)
-    thinking = False
-
-    for response in responses:
-        stream.process(response.token)
-
-        delta = stream.last_content_delta
-        ch = stream.current_channel
-
-        if ch == "analysis" and not thinking:
-            thinking = True
-            yield response.model_copy(update={"text": "<think>"})
-
-        if ch != "analysis" and thinking:
-            thinking = False
-            yield response.model_copy(update={"text": "</think>"})
-
-        if delta:
-            yield response.model_copy(update={"text": delta})
-
-        if response.finish_reason is not None:
-            if thinking:
-                yield response.model_copy(update={"text": "</think>"})
-            yield response
-            break
-
-
 EXO_RUNNER_MUST_FAIL = "EXO RUNNER MUST FAIL"
 EXO_RUNNER_MUST_OOM = "EXO RUNNER MUST OOM"
 EXO_RUNNER_MUST_TIMEOUT = "EXO RUNNER MUST TIMEOUT"
--- a/src/exo/worker/tests/unittests/test_runner/test_error_handling.py
+++ b/src/exo/worker/tests/unittests/test_runner/test_error_handling.py
@@ -1,50 +0,0 @@
-# pyright: reportAny=false
-from unittest.mock import MagicMock
-
-from exo.shared.types.chunks import TokenChunk
-from exo.shared.types.common import CommandId
-from exo.shared.types.events import ChunkGenerated
-from exo.worker.runner.runner import send_error_chunk_on_exception
-from exo.worker.tests.constants import MODEL_A_ID
-
-
-def test_send_error_chunk_on_exception_no_error() -> None:
-    event_sender = MagicMock()
-    command_id = CommandId()
-
-    with send_error_chunk_on_exception(
-        event_sender, command_id, MODEL_A_ID, device_rank=0
-    ):
-        _ = 1 + 1
-
-    event_sender.send.assert_not_called()
-
-
-def test_send_error_chunk_on_exception_catches_error() -> None:
-    event_sender = MagicMock()
-    command_id = CommandId()
-
-    with send_error_chunk_on_exception(
-        event_sender, command_id, MODEL_A_ID, device_rank=0
-    ):
-        raise ValueError("test error")
-
-    event_sender.send.assert_called_once()
-    call_args = event_sender.send.call_args[0][0]
-    assert isinstance(call_args, ChunkGenerated)
-    assert call_args.command_id == command_id
-    assert isinstance(call_args.chunk, TokenChunk)
-    assert call_args.chunk.finish_reason == "error"
-    assert call_args.chunk.error_message == "test error"
-
-
-def test_send_error_chunk_on_exception_skips_non_rank_zero() -> None:
-    event_sender = MagicMock()
-    command_id = CommandId()
-
-    with send_error_chunk_on_exception(
-        event_sender, command_id, MODEL_A_ID, device_rank=1
-    ):
-        raise ValueError("test error")
-
-    event_sender.send.assert_not_called()
--- a/src/exo/worker/utils/net_profile.py
+++ b/src/exo/worker/utils/net_profile.py
@@ -1,64 +1,49 @@
-import anyio
-import httpx
-from anyio import create_task_group
+import http.client
+
+from anyio import create_task_group, to_thread
 from loguru import logger

 from exo.shared.topology import Topology
 from exo.shared.types.common import NodeId

-REACHABILITY_ATTEMPTS = 3
-

 async def check_reachability(
    target_ip: str,
    expected_node_id: NodeId,
+    self_node_id: NodeId,
    out: dict[NodeId, set[str]],
-    client: httpx.AsyncClient,
 ) -> None:
    """Check if a node is reachable at the given IP and verify its identity."""
-    if ":" in target_ip:
-        # TODO: use real IpAddress types
-        target_ip = f"[{target_ip}]"
-    url = f"http://{target_ip}:52415/node_id"

-    remote_node_id = None
-    last_error = None
-
-    for _ in range(REACHABILITY_ATTEMPTS):
+    def _fetch_remote_node_id() -> NodeId | None:
+        connection = http.client.HTTPConnection(target_ip, 52415, timeout=1)
        try:
-            r = await client.get(url)
-            if r.status_code != 200:
-                await anyio.sleep(1)
-                continue
+            connection.request("GET", "/node_id")
+            response = connection.getresponse()
+            if response.status != 200:
+                return None

-            body = r.text.strip().strip('"')
-            if not body:
-                await anyio.sleep(1)
-                continue
+            body = response.read().decode("utf-8").strip()

-            remote_node_id = NodeId(body)
-            break
+            # Strip quotes if present (JSON string response)
+            if body.startswith('"') and body.endswith('"') and len(body) >= 2:
+                body = body[1:-1]

-        # expected failure cases
-        except (
-            httpx.TimeoutException,
-            httpx.NetworkError,
-        ):
-            await anyio.sleep(1)
-
-        # other failures should be logged on last attempt
-        except httpx.HTTPError as e:
-            last_error = e
-            await anyio.sleep(1)
-
-    if last_error is not None:
-        logger.warning(
-            f"connect error {type(last_error).__name__} from {target_ip} after {REACHABILITY_ATTEMPTS} attempts; treating as down"
-        )
+            return NodeId(body) or None
+        except OSError:
+            return None
+        except http.client.HTTPException:
+            return None
+        finally:
+            connection.close()

+    remote_node_id = await to_thread.run_sync(_fetch_remote_node_id)
    if remote_node_id is None:
        return

+    if remote_node_id == self_node_id:
+        return
+
    if remote_node_id != expected_node_id:
        logger.warning(
            f"Discovered node with unexpected node_id; "
@@ -76,33 +61,18 @@ async def check_reachable(
    topology: Topology, self_node_id: NodeId
 ) -> dict[NodeId, set[str]]:
    """Check which nodes are reachable and return their IPs."""
-
    reachable: dict[NodeId, set[str]] = {}
-
-    # these are intentionally httpx's defaults so we can tune them later
-    timeout = httpx.Timeout(timeout=5.0)
-    limits = httpx.Limits(
-        max_connections=100,
-        max_keepalive_connections=20,
-        keepalive_expiry=5,
-    )
-
-    async with (
-        httpx.AsyncClient(timeout=timeout, limits=limits) as client,
-        create_task_group() as tg,
-    ):
+    async with create_task_group() as tg:
        for node in topology.list_nodes():
            if not node.node_profile:
                continue
-            if node.node_id == self_node_id:
-                continue
            for iface in node.node_profile.network_interfaces:
                tg.start_soon(
                    check_reachability,
                    iface.ip_address,
                    node.node_id,
+                    self_node_id,
                    reachable,
-                    client,
                )

    return reachable
--- a/tests/headless_runner.py
+++ b/tests/headless_runner.py
@@ -89,12 +89,6 @@ async def assert_downloads():
    await sd.ensure_shard(
        await build_full_shard(MODEL_CARDS["gpt-oss-20b-4bit"].model_id)
    )
-    await sd.ensure_shard(
-        await build_full_shard(MODEL_CARDS["glm-4.7-8bit-gs32"].model_id)
-    )
-    await sd.ensure_shard(
-        await build_full_shard(MODEL_CARDS["minimax-m2.1-8bit"].model_id)
-    )


 async def ring_backend(test: Tests):
--- a/uv.lock
+++ b/uv.lock