TIL: Running TypeScript Directly With tsx

ts-node works. tsx is faster. It uses esbuild under the hood and handles ESM and CJS without config.

tsx sdk-example.ts

Runs a TypeScript file directly. The same as ts-node but with faster startup because esbuild skips type checking.

tsx watch sdk-example.ts

Watch mode restarts the script on file changes. Built in, no extra flag parade.

tsx src/server.ts

Runs a TypeScript server. Works with Express, Fastify, and most Node.js frameworks without modification.

How do I install tsx?

npm install -g tsx

Does tsx do type checking?

tsx does not type check by default. Run tsc separately in CI. tsx is for development speed, not for catching type errors.