Generate package.json#exports from src

Automatically generate package.json exports from your source files with support for TypeScript, JavaScript, JSX/TSX, and CSS. Features include index file flattening, custom transform modes, and monorepo live types support.

Install @ngrok/gen-x to your devDependencies with your preferred package manager:

# Generate exports from src/ to dist/
npx gen-x

# Preview changes without writing
npx gen-x --dry-run

This will scan your src/ directory and generate package.json exports like:

{
	"exports": {
		"./package.json": "./package.json",
		".": {
			"import": "./dist/index.js",
			"types": "./dist/index.d.ts"
		},
		"./utils": {
			"import": "./dist/utils.js",
			"types": "./dist/utils.d.ts"
		}
	}
}

• ✅ Index file flattening - index.ts → ".", lib/index.ts → "./lib"
• ✅ CSS support - Preserves extensions for assets, no types field
• ✅ Multiple file types - .ts, .tsx, .js, .jsx, .mjs, .cjs, .css
• ✅ Transform modes - camelCase, kebab-case, PascalCase, snake_case
• ✅ Replace patterns - Rename exports with regex or string patterns
• ✅ Custom conditions - For monorepo live types
• ✅ Watch mode - Automatically regenerate exports on file changes
• ✅ Source-only mode - Emit plain source file paths without import/types conditions
• ✅ Cross-platform - Always generates POSIX paths for package.json
• ✅ Collision detection - Errors on duplicate export keys

gen-x is configured entirely through CLI flags.

Options:
  -V, --version                      output the version number
  --dry-run, --dryRun               Preview changes to stdout
  --exclude <exclude...>            Globs to exclude (default: ["**/*.d.ts","**/*.test.*","**/*.spec.*","**/__tests__/**"])
  --include <include...>            Globs to include (default: ["**/*.{ts,tsx,cts,mts,js,jsx,mjs,cjs,css}"])
  -i, --input <input>               Input directory (default: "src")
  -m, --mode <mode>                 Transform mode: passthrough|camelCase|kebab-case|PascalCase|snake_case (default: "passthrough")
  --customCondition <condition>     Custom condition for monorepo live types
  -o, --output <output>             Output directory (default: "dist")
  -p, --package <package>           Path to package.json (default: "package.json")
  -r, --replace <pattern:=>replacement...>  Replace export keys
  --sourceOnly                      Only emit plain source file paths in exports
  -w, --watch                       Watch the input directory for changes and regenerate exports
  -h, --help                        display help for command

npx gen-x

# Transform to camelCase
npx gen-x --mode camelCase
# hello-world.ts → ./helloWorld

# Transform to kebab-case
npx gen-x --mode kebab-case
# HelloWorld.ts → ./hello-world

# Remove _pb suffix from protobuf files
npx gen-x --replace "/_pb/:=>"
# user_pb.ts → ./user (but still imports from user_pb.js)

# Multiple replacements
npx gen-x --replace "/_pb/:=>" --replace "/^api-/:=>api/"

For consuming packages in the same monorepo to use source TypeScript files:

npx gen-x --customCondition "@my-org/my-package/source"

Generates:

{
	"exports": {
		".": {
			"@my-org/my-package/source": "./src/index.ts",
			"import": "./dist/index.js",
			"types": "./dist/index.d.ts"
		}
	}
}

See Live Types in TypeScript Monorepo for more info.

CSS files automatically preserve their extensions:

# src/styles/theme.css → ./styles/theme.css
npx gen-x

Output:

{
	"./styles/theme.css": {
		"import": "./dist/styles/theme.css"
	}
}

# Include only TypeScript files
npx gen-x --include "**/*.ts" --include "**/*.tsx"

# Exclude internal files
npx gen-x --exclude "**/internal/**" --exclude "**/*.test.*"

Automatically regenerate exports when files are added, deleted, or renamed:

npx gen-x --watch

Writes are skipped when exports haven't changed, avoiding unnecessary downstream rebuilds in tools like Turborepo.

import { generateExports } from "@ngrok/gen-x";

const exports = await generateExports({
	input: "src",
	output: "dist",
	mode: "camelCase",
});

console.log(exports);

We use mise to manage the toolchain (Node.js and pnpm). Versions are pinned in .nvmrc (Node) and package.json#packageManager (pnpm), and locked in the committed mise.lock.

First, install mise (or run ./scripts/install-mise to install the pinned version):

For all other install methods, see the mise installation guide.

Don't forget to activate mise in your shell.

Next, clone the repo and move into the directory:

git clone https://github.com/ngrok/gen-x.git
cd gen-x

Next, run:

mise trust
mise install
mise run setup

This installs the pinned node and pnpm versions and then runs pnpm install --frozen-lockfile to install all node_modules.

Useful mise tasks:

• mise run doctor — verify the active tools match the committed pins
• mise run relock — refresh mise.lock after bumping .nvmrc or package.json#packageManager (then run mise install and commit both)