When working on Node.js, React, Next.js, or any modern application, one of the first things you'll create is a .env file.

It stores everything from database credentials to API keys and authentication secrets.

DATABASE_URL=postgres://...
JWT_SECRET=super-secret-key
STRIPE_SECRET_KEY=sk_live_xxxxxxxxx
NEXT_PUBLIC_API_URL=https://api.example.com

The problem?

You should never commit this file to Git.

But your teammates still need to know which environment variables are required to run the project.

That's why almost every project includes a .env.example.

The Problem

Keeping .env.example updated is surprisingly annoying.

Imagine adding a new environment variable.

REDIS_URL=redis://localhost:6379

Now you also need to remember to update:

REDIS_URL=

inside .env.example.

Most developers forget.

Eventually your repository looks like this:

❌ Missing variables
❌ Outdated documentation
❌ New contributors can't run the project

The Solution

I built gen-envex to solve exactly this problem.

Instead of maintaining .env.example manually, it generates one automatically from your existing .env.

Your secrets are removed, while the file structure stays exactly the same.

Input:

# Database
DB_HOST=localhost
DB_PORT=5432
DB_PASSWORD=mysecretpassword

# API
NEXT_PUBLIC_API_URL=https://api.example.com
STRIPE_SECRET_KEY=sk_live_xxxxx

Generated output:

# Database
DB_HOST=
DB_PORT=
DB_PASSWORD=

# API
NEXT_PUBLIC_API_URL=
STRIPE_SECRET_KEY=

Simple.

Safe.

Automatic.

Features

✅ Removes all secret values

✅ Preserves comments

✅ Preserves blank lines

✅ Maintains variable order

✅ Supports custom input/output files

✅ Works on Windows, macOS, and Linux

Installation

Install globally:

npm install -g gen-envex

Or use it without installing:

npx gen-envex

Or install it as a development dependency:

npm install --save-dev gen-envex

Basic Usage

Run:

gen-envex

or

npx gen-envex

This generates:

.env.example

from

.env

Custom Files

Need different file names?

gen-envex --input .env.local --output .env.example

or

gen-envex --input config/.env --output config/.env.example

Automate Everything

The best part is that you never have to think about it again.

Add it to your package.json.

{
  "scripts": {
    "dev": "gen-envex && next dev"
  }
}

Now every time you start your development server,

npm run dev

your .env.example is automatically updated.

No extra commands.

No forgotten variables.

No outdated examples.

Why This Matters

Open-source projects often receive issues like:

"The app doesn't start."

or

"Which environment variables do I need?"

In many cases, the answer is simply that .env.example wasn't updated.

Keeping it synchronized makes onboarding dramatically easier for teammates and contributors.

It's a tiny improvement that saves time for everyone.

Standalone Script

Don't want to install a package?

gen-envex also provides a standalone script.

Simply copy generate-env-example.js into your project and run:

node generate-env-example.js

You can even integrate it into your development workflow:

{
  "scripts": {
    "dev": "node generate-env-example.js && next dev"
  }
}

Open Source

If you find the project useful, I'd love your feedback.

⭐ GitHub: https://github.com/AniketDey06/gen-envex

📦 npm: https://www.npmjs.com/package/gen-envex

Issues, feature requests, and pull requests are always welcome.

Final Thoughts

Sometimes the best developer tools solve small problems that every developer has experienced.

gen-envex is one of those tools.

It removes one more thing you have to remember, keeps your repositories safer, and makes collaboration easier.

If you're tired of manually maintaining .env.example, give it a try.

Happy coding! 🚀