bun-freebsd

Build Bun natively on FreeBSD. Based on Li-Wen Hsu's claude/freebsd-support branch with additional patches for WebKit, bootstrap toolchain, and cmake wiring.

Build

git clone https://github.com/8ff/bun-freebsd.git
cd bun-freebsd
sh build.sh

Requires FreeBSD 13.2+ amd64, ~16 GB RAM, ~20 GB disk. The script installs all dependencies via pkg, clones the source trees, builds Bun's Zig fork, applies patches, and compiles Bun + WebKit/JSC.

Output: ~/src/bun/build/bun — a native FreeBSD ELF.

Running Claude Code

After building, grab cli.js from the npm package (while it's still available — Anthropic has said this is being deprecated):

mkdir -p ~/.npm-global
npm config set prefix ~/.npm-global
npm install -g @anthropic-ai/claude-code

Then run it under your native bun:

~/src/bun/build/bun ~/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js --version

For convenience, create a wrapper:

mkdir -p ~/.local/bin
cat > ~/.local/bin/claude <<'EOF'
#!/bin/sh
exec ~/src/bun/build/bun ~/.npm-global/lib/node_modules/@anthropic-ai/claude-code/cli.js "$@"
EOF
chmod +x ~/.local/bin/claude

Note: cli.js is Anthropic's proprietary code (not included in this repo). Anthropic has stated they plan to deprecate the npm package. This repo only contains the Bun build script and patches — sourcing cli.js is on you.

What the patches fix

~150 lines on top of lwhsu's branch:

• WebKit AvailableMemory.cpp — FreeBSD branch was using Linux-only struct sysinfo; replaced with sysctlbyname("hw.physmem")
• WebKit RAMSize.cpp — removed FreeBSD from #include <sys/sysinfo.h> guard (Linux-only header)
• SetupWebKit.cmake — pass USE_SYSTEM_MALLOC=ON to JSC on FreeBSD (lwhsu had a comment for this but never wired it)
• codegen-ts-node-runner.mjs — fix esbuild output format for Node bootstrap: strip __commonJS wrapper, remove init_define_* no-ops, disable keepNames to avoid __name() helper
• bundle-functions.ts — remove if (import.meta.main) guard that esbuild's --define constant-folds to if (true) in bundled output
• glob-sources-node.mjs (new) — Node port of Bun-requiring glob-sources.mjs for bootstrap on hosts without an existing Bun binary

Credit

• Li-Wen Hsu (@lwhsu) — ~90% of the FreeBSD port
• Upstream: oven-sh/bun, oven-sh/WebKit, oven-sh/zig