Matrix Drift Scans Across a Monorepo

In a monorepo, a single repository-wide DriftScore hides which package is drifting. A CI matrix runs one Vibgrate scan per package in parallel, using --cwd to target each workspace, so every package gets its own score and gate.

Prerequisites

• A monorepo with multiple packages, each with its own manifest and lockfile.
• Vibgrate running in CI and familiarity with matrix builds.

Steps

1. List the packages to scan

Decide which package directories to cover, for example packages/api and packages/web. These become the matrix values.

2. Define the matrix

Declare a matrix over the package directories so the job fans out, one run per package.

jobs:
  drift:
    strategy:
      matrix:
        pkg: [packages/api, packages/web]
    runs-on: ubuntu-latest

3. Scan each package with --cwd

Use --cwd to point the scan at the matrix package directory.

vg scan --cwd packages/api

In the workflow, reference the matrix value.

      - run: npx @vibgrate/cli scan --cwd ${{ matrix.pkg }}

4. Gate each package

Add a budget per package so one drifting package fails only its own matrix leg.

vg scan --cwd packages/api --drift-budget 60

5. Verify per-package results

Each matrix leg appears as its own job in the Actions UI with its own DriftScore, so you can see exactly which package is over budget.

Verification

Confirm the matrix produced one job per package and that each reports its own DriftScore. Push drift into a single package and verify only that matrix leg fails.

vg scan --cwd packages/web --drift-budget 60

Next Steps

• Cache .vibgrate per package to speed up repeated runs.
• Restrict PR matrix legs with vg scan --changed-only.
• Push each package's results to Vibgrate Cloud with vg scan --push.