---
type: Changed
pr: 537
---
Migrate 7 modules from hand-written CommonJS to TypeScript source of truth per ADR-457 (#537). Modules migrated: `gap-checker`, `docs`, `check-command-router`, `frontmatter`, `learnings`, `gsd2-import`, and `profile-pipeline`. Each `src/<m>.cts` compiles to a gitignored `get-shit-done/bin/lib/<m>.cjs` with behaviour preserved byte-for-behaviour; only strict types are added.

<!-- docs-exempt: Internal ADR-457 build-at-publish source migration; behaviourally-identical gitignored artifacts at same require() paths; no user-facing change. -->