Node.js CI on GitHub Actions

npm ci writes tens of thousands of small files on every run.

Why it happens

node_modules is a filesystem stress test, and network-attached CI storage is the worst possible place to run one.

What to change

1. Cache ~/.npm and restore node_modules directly rather than reinstalling
2. Move to pnpm — its content-addressed store makes installs near-instant on a warm cache
3. Run on a runner with local NVMe; this workload is disk-bound, not CPU-bound
4. Use --prefer-offline so a warm cache is not revalidated over the network

Node.js on runnerhut

jobs:
  test:
    runs-on: runnerhut-4vcpu-ubuntu-2404
    steps:
      - uses: actions/checkout@v4
      - uses: actions/setup-node@v4
        with: { node-version: 22, cache: npm }
      - run: npm ci --prefer-offline
      - run: npm test

The only runnerhut-specific line is `runs-on: runnerhut-4vcpu-ubuntu-2404`. Everything else is standard GitHub Actions — the same actions, the same secrets and the same permissions model you use today.