TypeScript execution environment for node
TypeScript JavaScript


TypeScript Node

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TypeScript execution environment and REPL for node. Works with typescript@>=1.5.


npm install -g ts-node

# Install a TypeScript compiler (requires `typescript` by default).
npm install -g typescript


  • Execute TypeScript files with node
  • Interactive REPL
  • Execute (and print) TypeScript through the CLI
  • Uses source maps
  • Loads compiler options and .d.ts files from tsconfig.json


# Execute a script as you would normally with `node`.
ts-node script.ts

# Starts the TypeScript REPL.

# Execute code with TypeScript.
ts-node -e 'console.log("Hello, world!")'

# Execute, and print, code with TypeScript.
ts-node -p '"Hello, world!"'

# Pipe scripts to execute with TypeScript.
echo "console.log('Hello, world!')" | ts-node

TypeScript REPL


mocha --compilers ts:ts-node/register,tsx:ts-node/register [...args]


ts-node node_modules/tape/bin/tape [...args]


# Just create a `gulpfile.ts` and run `gulp`.

How It Works

TypeScript Node works by registering the TypeScript compiler for the .ts, .tsx and - when allowJs is enabled - .js extensions. When node.js has a file extension registered (the require.extensions object), it will use the extension internally with module resolution. By default, when an extension is unknown to node.js, it will fallback to handling the file as .js (JavaScript).

P.S. This means that if you don't register an extension, it'll be compiled as JavaScript. When ts-node is used with allowJs, JavaScript files are transpiled using the TypeScript compiler.

Loading tsconfig.json

Typescript Node uses tsconfig.json automatically, use -n to skip loading tsconfig.json.

Configuration Options

You can set options by passing them in before the script.

ts-node --compiler ntypescript --project src --ignoreWarnings 2304 hello-world.ts
  • --project, -P Path to resolve tsconfig.json from (or false to disable) (also process.env.TS_NODE_PROJECT)
  • --compiler, -C Use a custom, require-able TypeScript compiler compatible with typescript@>=1.5.0-alpha (also process.env.TS_NODE_COMPILER)
  • --ignore Specify an array of regular expression strings for ts-node to skip compiling as TypeScript (defaults to /node_modules/, false to disable) (also process.env.TS_NODE_IGNORE)
  • --ignoreWarnings, -I Set an array of TypeScript diagnostic codes to ignore (also process.env.TS_NODE_IGNORE_WARNINGS)
  • --disableWarnings, -D Ignore all TypeScript errors (also process.env.TS_NODE_DISABLE_WARNINGS)
  • --compilerOptions, -O Set compiler options using JSON (E.g. --compilerOptions '{"target":"es6"}') (also process.env.TS_NODE_COMPILER_OPTIONS)
  • --fast, -F Use TypeScript's transpileModule mode (no type checking, but faster compilation) (also process.env.TS_NODE_FAST)
  • --lazy, -L Lazily defer TypeScript initialization until first .ts file
  • --no-cache Skip hitting the compiled JavaScript cache (also process.env.TS_NODE_CACHE)
  • --cache-directory Configure the TypeScript cache directory (also process.env.TS_NODE_CACHE_DIRECTORY)

Programmatic Usage

require('ts-node').register({ /* options */ })

// Or using the shortcut file.

This will register the TypeScript compiler for "on the fly" compilation support of .ts and .tsx files during the run of the script. From here you can use require to bring in modules from TypeScript files:

var someModule = require('path_to_a_typescript_file');