env-diff-cli

Compare .env files across environments — catch missing variables before deployment.

Install

npm install -g env-diff-cli

Usage

env-diff <file1> <file2> [options]
env-diff --check <template> <target>

Commands

Basic diff

env-diff .env .env.production

Shows missing, extra, and changed variables between the two files.

Missing only

env-diff .env .env.staging --missing-only

Only shows variables present in .env but absent in .env.staging.

Compare values

env-diff .env .env.production --values

Also compares values (secrets are masked as ***).

CI check mode

env-diff --check .env.example .env

Exits with code 1 if .env is missing any variables defined in .env.example. Perfect for CI/CD gates.

CI/CD Examples

Shell script

if env-diff --check .env.example .env; then
  echo "All required env vars present — deploying"
else
  echo "Missing env vars — aborting deploy"
  exit 1
fi

GitHub Actions

- name: Validate environment variables
  run: env-diff --check .env.example .env

GitLab CI

validate:
  script:
    - npx env-diff-cli --check .env.example .env

Docker entrypoint

#!/bin/sh
env-diff --check /app/.env.example /app/.env || exit 1
exec "$@"

Pre-deploy hook (package.json)

{
  "scripts": {
    "predeploy": "env-diff --check .env.example .env",
    "deploy": "..."
  }
}

Output

| Symbol | Meaning | |--------|---------| | - KEY (red) | Missing in second file | | + KEY (yellow) | Extra in second file (not in first) | | ~ KEY (yellow) | Present in both but different value | | ✓ KEY (green) | Present in both with same value |

Options

| Flag | Description | |------|-------------| | --missing-only | Only show vars in file1 missing from file2 | | --values | Compare values (masked with ***) | | --check | CI mode — exit 1 if target missing required vars | | --no-color | Disable ANSI color output | | -h, --help | Show help |

Exit Codes

| Code | Meaning | |------|---------| | 0 | No differences (or --check passed) | | 1 | Differences found (or --check failed) | | 2 | Error (file not found, bad arguments) |

.env Format Support

• KEY=VALUE
• export KEY=VALUE
• Quoted values: KEY="hello world", KEY='hello'
• Inline comments: KEY=value # this is ignored
• Comment lines: # full line comment
• Empty lines ignored

License

MIT