Main package ships all seven platform binaries: 53.56 MB download / 119.45 MB unpacked per install

Summary

agent-browser@0.39.1 (current latest) publishes all seven prebuilt binaries inside the main package, so every install downloads and unpacks every platform:

Registry facts:

• tarball: 53,561,140 B (~53.6 MB)
• unpacked: 119,447,219 B (~119.5 MB), 45 files (npm view agent-browser@0.39.1 dist)
• dependencies / optionalDependencies: none — the binaries are simply listed in files: ["bin", ...] of the main package
• the binaries are 99.7% of the unpacked payload, and any given host runs exactly one of them

Measured impact (Linux x64, node 26, pnpm 12.11.2)

• fetching the tarball directly: 53.56 MB in 0.87 s (61.8 MB/s) — the network is not the problem
• cold pnpm install -g agent-browser@0.39.1 with an empty store: 6.0–8.4 s, almost entirely time spent writing/unpacking ~119 MB (this machine does ~28 MB/s fsync writes)
• same command with a warm store: 0.09–0.12 s
• on a Linux x64 host the only usable binary is agent-browser-linux-x64 (18.3 MB; 7,714,144 B when gzipped with -9), so ~45 MB of the 53.56 MB download is for platforms that can never run here

A secondary effect of bundling the binaries in the main package is that a postinstall script is required (chmod + repoint the global symlink). pnpm ≥10 blocks dependency build scripts by default, so a global install with pnpm 12 stops on the interactive "Choose which packages to build" prompt — a cold install that takes 6 s when the prompt is answered immediately measured "Done in 15s" when the answer arrived 15 s later. The CLI itself keeps working (the JS wrapper chmods at runtime), so this is friction rather than breakage.

Suggestion

Publish per-platform packages (@agent-browser/linux-x64, @agent-browser/darwin-arm64, @agent-browser/win32-x64, ...) and reference them from optionalDependencies with os/cpu/libc fields — the pattern used by esbuild, @swc/core, rollup and rolldown. A Linux x64 install would then fetch ~8 MB instead of 53.56 MB and unpack ~18 MB instead of ~119 MB, and the postinstall script would no longer be needed on the normal path.

Related: #1422, #1577 (verification of the fallback postinstall download) — this report is about what the main tarball contains.

Reproduction

$ npm view agent-browser@0.39.1 dist --json
$ npm pack agent-browser@0.39.1            # 53.56 MB
$ ls -l node_modules/agent-browser/bin
$ gzip -9 -c node_modules/agent-browser/bin/agent-browser-linux-x64 | wc -c
7714144