feat: add Linux x64 and arm64 Homebrew support

[yetmike]

Summary

Adds prebuilt Linux binaries so brew install steipete/tap/summarize works on Linux x64 and arm64, not just macOS.

Three small, focused changes — no CI added, everything stays in the existing manual release flow.

Follow-up: steipete/homebrew-tap#18 restructures the formula with on_macos/on_linux blocks. Merge this PR first, cut a release, then merge that one.

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scripts/build-bun.js

• Added buildLinuxX64() / buildLinuxArm64() using bun-linux-x64 / bun-linux-arm64 compile targets
• Extracted shared buildPlatform() helper (all three platforms share identical logic)
• Cross-platform sha256() helper — shasum -a 256 on macOS, sha256sum on Linux
• detectNativePlatform() — auto-detects host so the existing pnpm build:bun:test on macOS is completely unchanged
• New --platform <macos-arm64|linux-x64|linux-arm64> flag for a single platform
• New --all flag to build all three in one run; native platform is always built last so dist-bun/summarize is the runnable binary for smoke tests
• New --test on --all only runs smoke tests against the native binary

package.json

Two new scripts that mirror the existing build:bun / build:bun:test convention:

build:bun:all       bun scripts/build-bun.js --all
build:bun:all:test  bun scripts/build-bun.js --all --test

scripts/release.sh tap

• sha256_file() helper works on macOS (shasum) and Linux (sha256sum)
• Downloads all three platform tarballs, computes their sha256s
• Rewrites the formula in full with on_macos/on_linux blocks (no more manual editing)
• Missing tarballs print a warning and are skipped
• Repo URL is derived from git remote get-url origin — works for any fork automatically

RELEASING.md

Step 3 now reads:

pnpm -s build:bun:all:test — builds macOS arm64 natively (smoke-tested) and cross-compiles linux-x64 and linux-arm64

Step 7 (gh release create) now includes all three Bun tarballs alongside the extension zips.
Step 8 (tap) now says to run bash scripts/release.sh tap instead of editing the formula by hand.

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How cross-compilation works

Bun supports cross-compilation out of the box. Running pnpm build:bun:all:test on your Mac:

1. Cross-compiles bun-darwin-arm64 → dist-bun/summarize-macos-arm64-v<ver>.tar.gz
2. Cross-compiles bun-linux-arm64 → dist-bun/summarize-linux-arm64-v<ver>.tar.gz
3. Builds bun-linux-x64 natively... wait, wrong — on macOS the native is macos-arm64, built last. On Linux x64 the native is linux-x64, built last. The native platform is always last so smoke tests run on the correct binary.

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Test plan

• pnpm build:bun:all:test on Linux x64 — all three tarballs built, smoke test + E2E pass on the x64 binary
• brew tap yetmike/tap && brew install summarize && summarize --version on Linux — works
• pnpm build:bun:all:test on macOS — builds all three tarballs, smoke-tests macOS binary
• bash scripts/release.sh tap fills in real sha256s and rewrites formula correctly
• pnpm build:bun:test on macOS still works exactly as before (no regression)

🤖 Generated with Claude Code

[yetmike]

Fix: 6189ac4 — --all mode now builds the native platform last.

Each build overwrites dist-bun/summarize in place (by design, so the tarball always contains a file named summarize). In --all mode this meant the last platform in the list clobbered the native binary before --test could run it. The fix reorders the build list so the native platform is always built last, leaving dist-bun/summarize as the runnable binary for smoke tests.

Verified on Linux x64: pnpm build:bun:all:test now builds macos-arm64 → linux-arm64 → linux-x64 (native last), then smoke-tests and E2E-passes the x64 binary.

[yetmike]

Fix: 1902177 — scripts/release.sh tap now skips missing platform blocks instead of writing sha256 "".

Tested the full flow on Linux (where no macOS tarball exists in the release):

• macOS tarball 404 → warning printed, on_macos block omitted entirely
• Linux x64 + arm64 downloaded, sha256 computed, written correctly
• brew uninstall && brew install from the rewritten formula — ✅ summarize --version → 0.11.2

On steipete's Mac, all three tarballs will be present so all three blocks will appear in the formula.

[yetmike]

Note on cross-compilation: pnpm build:bun:all:test works from either macOS or Linux — bun's cross-compilation is bidirectional. Running on Linux produces a valid bun-darwin-aarch64 binary alongside the Linux ones (we can see it in the build log: compile dist-bun/summarize bun-darwin-aarch64-v1.3.9). The --test flag only smoke-tests the native binary, but all three tarballs are produced either way.

One outstanding item in the test plan that requires a Mac: verify the macOS binary cross-compiled from Linux actually runs on Apple Silicon. Everything else has been tested on Linux x64.

[uniuuu]

Hi @steipete @yetmike
Run into same issue when do openclaw onboard --install-daemon while selecting summarize

summarize: The arm64 architecture is required for this software.
Error: summarize: An unsatisfied requirement failed this build.

no other skills failed during onboarding.

And npm i -g @steipete/summarize also works.

[steipete]

Homebrew is only meant for macOS. Use npm for other OSes

[yetmike]

Homebrew does support Linux

Let me check the openclaw errors and come with the fix