Use affected mode

Optimize CI pipelines by running tasks only on packages affected by code changes. Use the --affected flag in Turborepo commands to automatically filter tasks to packages with changes, significantly reducing CI execution time in large monorepos.

# Run build only on affected packages
turbo run build --affected

# Specify custom base branch for comparison
TURBO_SCM_BASE=development turbo run test --affected

By default, affected mode compares changes between main and HEAD. Override these defaults with environment variables TURBO_SCM_BASE and TURBO_SCM_HEAD when needed, such as when working with feature branches or alternative main branches.

Ensure your checkout has sufficient history depth; shallow clones may cause all packages to be considered changed. This approach ensures CI resources are used efficiently by focusing only on what changed, preventing unnecessary builds and tests while maintaining comprehensive validation.