From daa8fff5f398d9ec5455191dc034c5405b654dca Mon Sep 17 00:00:00 2001
From: Navid EMAD <navid.emad@yespark.fr>
Date: Thu, 21 May 2026 14:39:25 +0200
Subject: [PATCH] Add ZIGFLAGS= make download-v8 to fetch prebuilt V8 and skip
 the source build

---
 .gitignore |  1 +
 Makefile   | 34 +++++++++++++++++++++++++++++++++-
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/.gitignore b/.gitignore
index 48403d38..c23d7cc4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
 /.zig-cache/
 /.lp-cache/
+/v8/
 /zig-pkg/
 zig-out
 lightpanda.id
diff --git a/Makefile b/Makefile
index 9daa2c75..4f30d2fd 100644
--- a/Makefile
+++ b/Makefile
@@ -33,6 +33,27 @@ else
 endif
 
 
+# Prebuilt V8
+# -----------
+# Building V8 from source takes 10+ minutes. `make download-v8` fetches the
+# matching prebuilt archive from the zig-v8-fork releases instead. The versions
+# are read from the install action so they can't drift from CI.
+V8_ACTION := .github/actions/install/action.yml
+V8_VERSION := $(shell awk -F\' '/^  v8:/{f=1} f&&/default:/{print $$2; exit}' $(V8_ACTION))
+ZIG_V8_TAG := $(shell awk -F\' '/^  zig-v8:/{f=1} f&&/default:/{print $$2; exit}' $(V8_ACTION))
+V8_ARCHIVE := libc_v8_$(V8_VERSION)_$(OS)_$(ARCH).a
+V8_CACHE   := .lp-cache/prebuilt-v8/$(V8_ARCHIVE)
+V8_LINK    := v8/libc_v8.a
+
+# If the prebuilt archive is in place and the caller hasn't set ZIGFLAGS, link
+# against it (the same flag CI passes) rather than building V8 from source.
+ifeq ($(strip $(ZIGFLAGS)),)
+  ifneq ($(wildcard $(V8_LINK)),)
+    ZIGFLAGS := -Dprebuilt_v8_path=$(V8_LINK)
+  endif
+endif
+
+
 # Infos
 # -----
 .PHONY: help
@@ -52,7 +73,18 @@ help:
 
 # $(ZIG) commands
 # ------------
-.PHONY: build build-v8-snapshot build-dev run run-release test bench data end2end clean
+.PHONY: build build-v8-snapshot build-dev download-v8 run run-release test bench data end2end clean
+
+## Download the prebuilt V8 archive (skips the 10+ min source build)
+download-v8:
+	@mkdir -p $(dir $(V8_CACHE)) $(dir $(V8_LINK))
+	@test -f $(V8_CACHE) || ( \
+		printf "\033[36mDownloading prebuilt V8 $(V8_VERSION) ($(ZIG_V8_TAG))...\033[0m\n"; \
+		curl -fL --progress-bar -o $(V8_CACHE) \
+			https://github.com/lightpanda-io/zig-v8-fork/releases/download/$(ZIG_V8_TAG)/$(V8_ARCHIVE) \
+		|| (rm -f $(V8_CACHE); printf "\033[33mDownload ERROR\033[0m\n"; exit 1) )
+	@ln -sf $(abspath $(V8_CACHE)) $(V8_LINK)
+	@printf "\033[33mV8 ready: %s -> %s\033[0m\n" "$(V8_LINK)" "$(V8_CACHE)"
 
 ## Build v8 snapshot
 build-v8-snapshot: