env-lint-cli 🔍

Lint and validate your .env files against .env.example. Find missing vars, extra vars, empty values, and type mismatches instantly.

Why?

Ever deployed and realized you forgot to set DATABASE_URL? Or had a teammate onboard with a stale .env? env-lint catches these issues before they become runtime errors.

Install

npm install -g env-lint-cli

Usage

# Compare .env with .env.example (default)
env-lint

# Compare specific files
env-lint .env.staging .env.example

# Full audit with type checking
env-lint --types --verbose

# Use in CI (fails on any issue)
env-lint --strict

What it checks

| Check | Flag | Description | |-------|------|-------------| | Missing vars | always | Variables in .env.example but not in .env | | Extra vars | always | Variables in .env but not in .env.example | | Empty values | always | Vars that are empty but have example values | | Type mismatches | --types | Different types between files (url vs string, boolean vs integer, etc.) |

Example Output

🔍 env-lint: comparing .env against .env.example

✗ 2 missing variable(s):
  MISSING DATABASE_URL (example: postgresql://localhost:5432/mydb)
  MISSING REDIS_URL (example: redis://localhost:6379)

⚠ 1 extra variable(s) not in example:
  EXTRA   DEBUG_MODE

⚠ 1 empty variable(s) that should have values:
  EMPTY   API_KEY (example: your-api-key-here)

2 error(s) | 2 warning(s) | 3/5 variables matched

Options

-t, --types     Check type consistency between files
-v, --verbose   Show detailed variable listing
-s, --strict    Treat warnings as errors (for CI)
-h, --help      Show help
--version       Show version

CI Integration

# GitHub Actions
- run: npx env-lint-cli --strict

// package.json
{
  "scripts": {
    "env:check": "env-lint --strict"
  }
}

License

MIT © kszongic

Support

If this tool saved you from a deployment disaster, consider sponsoring! ❤️