CI project invalidation

Bleep can compute exactly which projects are affected by a set of changes, so your CI pipeline only rebuilds and retests what's necessary.

Usage

bleep build invalidated --base <commitish>

The --base parameter is a git commitish — typically the base branch of a PR:

# Compare against the main branch
bleep build invalidated --base origin/main

# Compare against a specific commit
bleep build invalidated --base abc1234

Output is one project name per line, ready for piping:

bleep build invalidated --base origin/main | xargs bleep compile
bleep build invalidated --base origin/main | xargs bleep test

Use --json for structured output:

bleep build invalidated --base origin/main --json
# ["bleep-core","bleep-cli","bleep-tests"]

What counts as "invalidated"

A project is invalidated if any of the following changed between the base commit and HEAD:

1. Build configuration — dependencies, Scala/Java/Kotlin version, compiler options, platform settings, templates, or any other field in bleep.yaml that affects the project
2. Source files — any file under the project's source or resource directories was added, modified, or deleted (detected via git diff)
3. Transitive dependents — if project A changed, every project that depends on A (directly or transitively) is also invalidated. This includes sourcegen script dependencies.

New projects (present in HEAD but not in the base) are always invalidated.

GitHub Actions example

jobs:
  build:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0  # Full history needed for git diff

      - uses: bleep-build/bleep-setup-action@v1

      - name: Find affected projects
        id: affected
        run: |
          PROJECTS=$(bleep build invalidated --base origin/${{ github.event.pull_request.base.ref }})
          echo "projects=$PROJECTS" >> "$GITHUB_OUTPUT"
          if [ -z "$PROJECTS" ]; then
            echo "No projects affected"
          else
            echo "Affected projects:"
            echo "$PROJECTS"
          fi

      - name: Compile affected projects
        if: steps.affected.outputs.projects != ''
        run: bleep build invalidated --base origin/${{ github.event.pull_request.base.ref }} | xargs bleep compile

      - name: Test affected projects
        if: steps.affected.outputs.projects != ''
        run: bleep build invalidated --base origin/${{ github.event.pull_request.base.ref }} | xargs bleep test

GitLab CI example

build:
  script:
    - PROJECTS=$(bleep build invalidated --base origin/$CI_MERGE_REQUEST_TARGET_BRANCH_NAME)
    - |
      if [ -n "$PROJECTS" ]; then
        echo "$PROJECTS" | xargs bleep compile
        echo "$PROJECTS" | xargs bleep test
      else
        echo "No projects affected, skipping build"
      fi

How it works

1. Loads bleep.yaml from the base commit via git show
2. Compares the fully expanded project configuration (after template application) between base and HEAD
3. Runs git diff --name-only to detect changed source and resource files
4. Maps changed files to their owning projects
5. Computes the transitive closure of dependents for all directly affected projects