Env Manager

You are a DevOps engineer managing environment variables across development, staging, and production environments. The user wants to create a robust system for loading, validating, and switching between environment configurations without exposing secrets.

What to check first

• Check if a .env file exists in your project root: ls -la | grep .env
• Verify Node.js version supports your chosen dotenv library: node --version (need v14+)
• Confirm .env files are in .gitignore to prevent accidental secret commits: cat .gitignore | grep .env

Steps

1. Install dotenv package: npm install dotenv (loads .env files into process.env)
2. Create environment-specific files: .env.development, .env.staging, .env.production, and .env.example
3. In .env.example, list all required variables without values for documentation: DATABASE_URL= API_KEY= NODE_ENV=
4. At the very top of your application entry point (before other imports), add require('dotenv').config({ path: \.env.${process.env.NODE_ENV || 'development'}` })`
5. Create an env-validator.js file that checks all required variables are set using process.env[key]
6. Run the validator on startup: call it in your main server file before listening
7. Add npm scripts for each environment: "dev": "NODE_ENV=development node server.js", "start:staging": "NODE_ENV=staging node server.js"
8. Use process.env.VARIABLE_NAME throughout your code to access loaded variables

Code

// env-validator.js
const requiredVars = [
  'DATABASE_URL',
  'API_KEY',
  'JWT_SECRET',
  'NODE_ENV',
  'PORT'
];

function validateEnvironment() {
  const missing = requiredVars.filter(
    variable => !process.env[variable]
  );

  if (missing.length > 0) {
    console.error(
      `❌ Missing required environment variables: ${missing.join(', ')}`
    );
    process.exit(1);
  }

  console.log(`✅ Environment validated for ${process.env.NODE_ENV}`);
}

module.exports = validateEnvironment;

// server.js (entry point)
require('dotenv').config({
  path: `.env.${process.env.NODE_ENV || 'development'}`
});

const validateEnvironment = require('./env-validator');
validateEnvironment();

const express = require('express');
const app = express();
const port = process.env.PORT || 3000;

app.get('/health', (req, res) => {
  res.json({ 
    status: 'ok',
    environment: process.env.NODE_ENV,
    dbConnected: !!process.env.

Note: this example was truncated in the source. See the GitHub repo for the latest full version.

Common Pitfalls

• Treating this skill as a one-shot solution — most workflows need iteration and verification
• Skipping the verification steps — you don't know it worked until you measure
• Applying this skill without understanding the underlying problem — read the related docs first

When NOT to Use This Skill

• When a simpler manual approach would take less than 10 minutes
• On critical production systems without testing in staging first
• When you don't have permission or authorization to make these changes

How to Verify It Worked

• Run the verification steps documented above
• Compare the output against your expected baseline
• Check logs for any warnings or errors — silent failures are the worst kind

Production Considerations

• Test in staging before deploying to production
• Have a rollback plan — every change should be reversible
• Monitor the affected systems for at least 24 hours after the change