updating-fast-webstreams

name: updating-fast-webstreams description: Vendors fast-webstreams from npm to additions/, converting ESM to CommonJS with primordials for Node.js bootstrap. Use when the WebStreams version needs update or builds fail with streams errors. user-invocable: true allowed-tools: Bash(pnpm:), Bash(npm:), Bash(git:), Bash(node:), Bash(rg:), Bash(grep:), Bash(find:), Bash(ls:), Bash(cat:), Bash(head:), Bash(tail:), Bash(wc:), Bash(diff:*), Read---

updating-fast-webstreams

Synchronize experimental-fast-webstreams from node_modules to the vendor directory, converting ES modules to CommonJS for Node.js internal module system.

Vercel's library replaces Node.js pure-JS WebStreams with native C++ stream-backed implementations (3-15x faster).

Key Constraints

• Use absolute internal paths: require('internal/deps/fast-webstreams/utils') not require('./utils.js')
• Use individual exports.X = X; at file end (not module.exports = {})
• The sync script handles ES-to-CJS conversion and primordials transforms automatically
• Do not modify converted files manually; re-run sync instead

Process

Sync

node packages/node-smol-builder/scripts/vendor-fast-webstreams/sync.mts

Build (skip in CI)

pnpm --filter node-smol-builder clean && pnpm --filter node-smol-builder build

Validate

Quick (15 tests): node packages/node-smol-builder/scripts/vendor-fast-webstreams/validate.mts

Full WPT (1,116 tests): pnpm --filter node-smol-builder run wpt:streams (options after --: --force, --filter=, --verbose). Also wired into pnpm test via test/integration/wpt-streams.test.mts (gated on a built binary being present).

Update Version

1. Edit packages/node-smol-builder/package.json devDependencies
2. pnpm install
3. Run sync, clean, rebuild, validate

Circular Dependencies

Two cycles require special handling (managed by sync.mts):

• patch.js <-> index.js: Import directly from source modules, not index.js
• writer.js <-> writable.js: Use module reference pattern (access at runtime, not load time)

Key Files