tsenv

Type-check environment variables against TypeScript schemas.

日本語版 README はこちら (Japanese README)

Installation

npm install -D tsenv
# or
pnpm add -D tsenv
# or
yarn add -D tsenv

Usage

1. Define your environment variable types

Create a TypeScript file that exports your environment variable schema:

// env.ts
type Env = {
    API_URL: string
    ASSET_URL: string
    PORT?: number
    DEBUG?: boolean
}

export default Env

2. Create a configuration file

Create tsenv.config.js in your project root:

// tsenv.config.js
module.exports = {
    schema: './env.ts',      // Path to your type definition
    files: ['./env/**']      // Glob patterns for env files to check
}

Or if you're using TypeScript with tsx/ts-node:

// tsenv.config.ts
export default {
    schema: './env.ts',
    files: ['./env/**']
}

3. Run the type checker

npx tsenv check

You can also specify a custom config file:

npx tsenv check -c ./custom-config.ts

Features

• ✅ Type checking for string, number, and boolean types
• ✅ Optional properties support (using ?)
• ✅ Multiple env files support with glob patterns
• ✅ Clear error reporting with file locations
• ✅ Missing required variables detection
• ✅ Undefined variables detection

Example

See the example directory for a complete working example.

Error Types

Missing Required Variables

Variables defined as required in the schema but not found in any env file.

Type Mismatches

Variables with values that don't match their expected types.

Undefined Variables

Variables found in env files but not defined in the schema.

License

MIT