tsx
Node.js enhanced with esbuild to run TypeScript & ESM
Features
- Blazing fast on-demand TypeScript & ESM compilation
- Works in both CommonJS and ESM packages
- Supports next-gen TypeScript extensions (
.cts
& .mts
) - Supports
node:
import prefixes - Hides experimental feature warnings
- TypeScript REPL
- Tested on Linux & Windows with Node.js v12~18
Install
npm install --save-dev tsx
Install globally
Install it globally to use it anywhere, outside of your npm project, without npx.
npm install --global tsx
Usage
Note: Commands are prefixed with npx
to execute the tsx
binary, but it's not necessary if globally installed or when using it in the script
object in package.json
Run TypeScript / ESM / CJS module
Pass in a file to run:
npx tsx ./file.ts
Watch mode
Run file and automatically re-run on changes.
All imported files are watched except from the following directories:
node_modules
, bower_components
, vendor
, dist
, and .*
(hidden directories).
Press Return to manually re-run.
npx tsx watch ./file.ts
REPL
Start a TypeScript REPL by running tsx
with no arguments.
npx tsx
Cache
Modules transformations are cached in the system cache directory (TMPDIR
). Transforms are cached by content hash so duplicate dependencies are not re-transformed.
Set the --no-cache
flag to disable the cache:
npx tsx --no-cache ./file.ts
Node.js Loader
tsx is a standalone binary used in-place of Node.js, but sometimes you'll want to use node
directly. For example, when adding TypeScript & ESM support to Node.js binaries.
To use tsx with Node.js, pass it into the --loader
flag.
Note: Node.js's experimental feature warnings will not be suppressed when used as a loader
node --loader tsx ./file.ts
NODE_OPTIONS='--loader tsx' node ./file.ts
If you're looking to use the -r, --require
flag, you can use @esbuild-kit/cjs-loader
but transformations will not be applied to dynamic import()
s.
Dependencies
FAQ
Does it do type-checking?
No, esbuild does not support type checking.
It's recommended to run TypeScript separately as a command (tsc --noEmit
) or via IDE IntelliSense.
How is tsx
different from ts-node
?
They are both tools to run TypeScript files.
The main difference is that tsx
is powered by esbuild for blazing fast TypeScript compilation. Whereas ts-node
uses the TypeScript compiler, which is not as fast.
Because esbuild doesn't do type checking, tsx
is more equivalent to ts-node --transpileOnly
.
If you migrated from ts-node
, please share your performance gains here!