amaroc

CLI tool and wrapper for Node.js amaro to transpile TypeScript codebases to JavaScript via type stripping (preserving line numbers).

When publishing Node.js packages written in TypeScript, you often need to ship JavaScript files with source maps. amaroc simplifies this by stripping TypeScript types with amaro and rewriting .ts imports to .js using jscodeshift, all in a single command, removing the need for source maps. It’s perfect for prepack scripts and respects .gitignore for seamless use.

Note that Node.js 23 or newer is required for TypeScript support without transpilation, but this package will work on Node.js 20+ so you can use it in release CI workflows with older Node.js versions.

Features

• Transpiles .ts to .js with type stripping, preserving line numbers.
• Updates import, require(), and dynamic import() paths from .ts to .js.
• Respects .gitignore patterns to skip ignored files.
• Optional cleanup of original .ts files.
• Easy to drop in and use -- no tsconfig.json or other config required

Install

Install as a dev dependency:

npm install -D amaroc

Usage

After installing as a dev dep, it's as simple as adding this to your package.json's prepack to auto build before npm publish and on local npm installs:

{
  ...
  "prepack": "amaroc"
  ...
}

CLI

$ npx amaroc --help
Usage: amaroc [path] [options]

Description:
  Transpiles TypeScript (.ts) files to JavaScript (.js) files.

Arguments:
  [path]            Optional. A directory or a .ts file to transpile.
                    - If omitted, processes all .ts files in the current directory.
                    - If a directory, processes all .ts files in that directory.
                    - If a .ts file, converts only that file.

Options:
  --verbose         Enable debug logging during conversion.
  --clean           Delete original .ts files after conversion.
  --help            Display this help message.

Examples:
  amaroc                # Transpile all .ts files in current directory
  amaroc src            # Transpile all .ts files in 'src' directory
  amaroc file.ts        # Transpile 'file.ts' to 'file.js'
  amaroc --verbose      # Transpile with logging
  amaroc src --clean    # Transpile and delete original .ts files
  amaroc file.ts --verbose --clean  # Transpile single file with logging and cleanup

API

You can also use amaroc programmatically in Node.js:

const { convert, convertFile } = require('amaroc');

// Convert all .ts files in a directory
await convert('src', { debug: true, deleteOriginal: false });

// Convert a single file
const jsPath = convertFile('path/to/file.ts');

TypeScript Support

Type definitions are included:

import { convert, convertFile } from 'amaroc';

convert('src', { debug: true }).then(() => console.log('Done'));
const jsPath = convertFile('path/to/file.ts');

See index.d.ts for full type details.

License

MIT License. See LICENSE for details.

Acknowledgments

• Built on top of Node.js's amaro for type stripping.
• Uses Meta's jscodeshift for AST transformations.