Use when setting up or scaling a monorepo's build tooling — task graph, caching, affected/incremental builds, workspace boundaries, and release — in a touchstone repo. Triggers on turbo.json, nx.json, WORKSPACE/BUILD (Bazel/Buck2), pnpm-workspace.yaml, go.work, or an apps/ + packages/ layout. The monorepo-vs-polyrepo topology decision lives in the git-workflow skill; CI wiring in the ci-cd skill.
