Node

Owns the Node 25 install used by tools that don't run on Bun. The dean-stack app itself never executes on Node — it ships as static files to GitHub Pages. Node exists here strictly to host build/CI tools that haven't been ported to Bun.

When to invoke

• Asked to set Node version for the repo (.nvmrc, engines.node).
• A tool refuses to run on Bun and you need to confirm it can run on Node 25.
• CI workflow needs actions/setup-node.
• Diagnosing a "tool requires Node X" error during install or build.
• Someone asks whether to add .tool-versions, a volta block, or otherwise "enforce" a version manager — see below.

Owns

Node 25 install, version pinning via .nvmrc, the actions/setup-node invocation in CI, and the rule that Node is only for tooling — never a runtime target.

Defers to

• bun — for everything that can run on Bun (almost everything in this stack).
• bun-package-manager — for installing deps (bun install, not npm install).
• nitro — for build-time tooling that may bridge through Node (CI uses Node 20+ per the upstream Nitro doc).
• turborepo — for orchestrating Node-hosted tools alongside Bun-hosted ones.

Dean-stack rules

• Pillar 4 (CLI-gate-first) means: if a Node-hosted tool is in the gate, its CLI must obey the same zero-warning rule (no warnings, non-zero on any finding).
• Node is tooling-only. The app runtime is the browser; the script runtime is Bun. Do not introduce a node server, a node:test suite, or a Node-hosted dev server.
• .nvmrc is the single source of truth for the Node version. CI reads it (actions/setup-node@v4 with node-version-file: ".nvmrc"); locally, contributors use nvm. The repo does NOT ship a parallel .tool-versions file or a volta block in package.json — adding either would create a second pin to keep in sync.
• The version manager itself is a per-developer concern, not a project dep — it's a shell tool installed globally, never an npm dependency.

Patterns

.nvmrc for the repo (the only Node pin)

25

A single major number. CI's actions/setup-node reads this; local nvm reads it via nvm use. Don't add a second pin elsewhere.

CI: install Node alongside Bun

# .github/workflows/check.yml (excerpt)
- uses: actions/setup-node@v4
  with: { node-version-file: ".nvmrc" }
- uses: oven-sh/setup-bun@v2
  with: { bun-version-file: "package.json" }
- run: bun install --frozen-lockfile
- run: bun run check

Both runtimes coexist. Bun is the executor for bun run check; Node is available for any tool the gate invokes that demands it. CI doesn't use any version-manager wrapper — actions/setup-node reads .nvmrc directly.

When a tool demands Node

1. Verify it actually fails on Bun (try bunx <tool> first).
2. If it does, invoke it via a Node binary explicitly: node ./node_modules/<tool>/bin/<tool>.
3. Wrap that in a bun run-able npm script so Turbo still orchestrates it.
4. Document the Node-dependency in a script comment.

Anti-patterns

• Don't add a .tool-versions file — .nvmrc already pins Node, and asdf-nodejs supports .nvmrc natively via its legacy_version_file setting. A second pin file is a maintenance hazard, not a feature.
• Don't add a "volta": {...} block to package.json — Volta reads .nvmrc for the Node version on its own, and Bun is already pinned via packageManager. The block would duplicate both pins.
• Don't add asdf, Volta, nvm, fnm, or any version manager to package.json deps — they're shell tools installed globally per developer, not npm packages. They cannot be peerDependencies and should not be devDependencies.
• Don't write a node server — the app is static (see nitro for the GH Pages preset).
• Don't use node:test — bun test is the unit-test runner (see bun-test).
• Don't use npm/pnpm/yarn to install — Bun owns the package manager (see bun-package-manager).
• Don't pin Node below 22 — Node 22 LTS is the floor; 25 Current is the target.
• Don't recommend nodemon/tsx/dotenv — Bun covers these. If the user has Node-only tooling, use Node directly, but don't reach for the Node convenience wrappers.

Triggers on

node 25, node version, .nvmrc, .tool-versions, volta, asdf, node tooling, node toolchain