dbt CI on GitHub Actions

dbt parses the entire project and re-runs unchanged models.

Why it happens

The dbt manifest is not persisted, so state-based selection cannot work.

What to change

1. Cache target/manifest.json from the previous run and use state:modified selection
2. Cache the dbt packages directory keyed on packages.yml
3. Run tests only on modified models and their children

dbt on runnerhut

jobs:
  build:
    runs-on: runnerhut-4vcpu-ubuntu-2404
    steps:
      - uses: actions/checkout@v4
      - run: dbt deps
      - run: dbt build --select state:modified+ --state ./prod-manifest

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.