Agent skill · software engineering · cursor
principle-migrate-callers-then-delete-legacy-apis
Apply when introducing a new internal API while old callers still exist. Migrate callers and delete the old API in the same wave instead of preserving compatibility layers.
Why this skill is useful
Codifies a specific migration strategy for API refactoring that the AI could infer but now doesn't have to guess.
What it needs
About 1k tokens when loaded. Last updated 2026-08-06. 2,555 stars on the source repository.
What this skill does
Migrate Callers Then Delete Legacy APIs When we decide a new API is the right design, migrate callers and remove the old API in the same refactor wave instead of preserving compatibility layers. Rule: Do not keep legacy API paths only because internal callers still exist Inventory callers, migrate them, and delete the old API immediately Treat temporary adapters as exceptional and time-boxed, not default architecture Update tests to assert the new contract, and delete tests that only protect pre-refactor implementation details When this applies: No external users depend on backward compatibility The project can absorb coordinated breaking changes The new API is part of a simplification or refactor initiative Keeping both old and new APIs creates dual-path complexity, slows cleanup, and makes the codebase feel append-only.
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills cursor/principle-migrate-callers-then-delete-legacy-apis