env-type-gen-cli

Automatically generate TypeScript declarations (env.d.ts) for your environment variables from .env files. Keep your process.env type-safe without manual overhead.

Features

• 🚀 Auto-inference: Infers boolean, number, and string types.
• 👀 Watch Mode: Updates your types automatically as you edit your .env file.
• ⚡ Zero Dependencies: Blazingly fast and no package bloat.
• 🛠️ Custom Output: Specify custom input and output paths.

Installation

npm install -g env-type-gen-cli
# OR
npm install --save-dev env-type-gen-cli

Usage

Simple Usage

Run in your project root:

npx env-type-gen-cli

This generates an env.d.ts file from your .env.

Watch Mode

Keep your types in sync automatically:

npx env-type-gen-cli --watch

Custom Path

If your env file is not named .env:

npx env-type-gen-cli .env.local --out types/env.d.ts

Generated Output Example

For a .env like:

PORT=3000
DEBUG=true
DB_URL=mongodb://localhost:27017

It generates:

declare namespace NodeJS {
  interface ProcessEnv {
    PORT: number | string;
    DEBUG: boolean | string;
    DB_URL: string;
  }
}

License

MIT