Ruby CI on GitHub Actions

bundle install compiles native gems from source on every run.

Why it happens

Gems like nokogiri, pg and grpc build C extensions, which costs minutes unless the built gems are cached.

What to change

1. Cache vendor/bundle keyed on Gemfile.lock so native extensions are built once
2. Set bundle config deployment true for reproducible, lockfile-exact installs
3. Run RSpec in parallel with parallel_tests across all available cores
4. Use a snapshot runner if install still dominates — it removes the step entirely

Ruby on runnerhut

jobs:
  test:
    runs-on: runnerhut-8vcpu-ubuntu-2404
    steps:
      - uses: actions/checkout@v4
      - uses: ruby/setup-ruby@v1
        with: { ruby-version: '3.3', bundler-cache: true }
      - run: bundle exec parallel_rspec spec/

The only runnerhut-specific line is `runs-on: runnerhut-8vcpu-ubuntu-2404`. Everything else is standard GitHub Actions — the same actions, the same secrets and the same permissions model you use today.