Testloom

Testloom reads your coverage report, picks the least tested functions with the most callers and writes tests for them in your existing framework and style. Each generated test is run before it is proposed, and tests that pass trivially or only mirror the implementation are discarded.

Teams inheriting a codebase with thin coverage, or preparing for a large refactor, use it to build a safety net quickly. It opens small pull requests grouped by module so reviews stay manageable. It is strongest in TypeScript, Python, Go and Java; it struggles with code that depends heavily on global state or real network calls, where it suggests seams to add instead.