Native TypeScript Support for node:test

Wallaby now supports Node.js built-in TypeScript type stripping for node:test projects running Node v22.18 or later. TypeScript tests using .ts, .mts, and .cts files work in both CommonJS and ESM projects without an additional dependency, Node.js flag, or Wallaby configuration.

Wallaby continues to use a supported third-party TypeScript loader when one is installed. When no supported loader is available, Wallaby automatically uses Node.js built-in type stripping.

Node.js built-in type stripping supports erasable TypeScript syntax and does not perform type checking, read tsconfig.json, apply path aliases, transform code for older runtimes, or support .tsx files. Projects that require these features can continue to use a supported third-party loader.

Read more in the node:test docs.