🚀 Parity CLI

Stop "It works on my machine" — Enforce environment consistency across your team and CI

🎯 What is Parity?

Parity is a zero-config developer experience tool that ensures every engineer on your team—and your CI pipeline—runs the exact same environment configuration. It prevents:

• ❌ Runtime version mismatches
• ❌ Missing .env variables
• ❌ Package manager conflicts

⚡ Quick Start

1. Install

npm install -D parity-ci

2. Initialize

Generate a .env.lock file based on your current machine:

npx parity init

3. Run It

Option A: Check manually

npx parity check

Option B: Protect your start command (Recommended) Wrap your start script so checks run automatically before your app starts.

npx parity start npm run dev

🛠️ Configuration (How to write .env.lock)

The .env.lock file allows you to define strict rules for your project.

[!IMPORTANT] > Syntax Warning: Use YAML syntax (key: value), NOT .env syntax (KEY=VALUE).

Example Configuration

# 1. Runtime Enforcement
runtime:
  name: node
  version: ">=18.0.0"
  manager: npm # Optional: Enforce specific manager

# 2. OS Restrictions (Optional)
os: ["darwin", "linux"]

# 3. Environment Files
envFiles:
  - .env
  - .env.local

# 4. Environment Variables
env:
  DATABASE_URL: required
  API_KEY: required
  DEBUG: optional

Configuration Types & Allowed Values

| Option | Type | Allowed Values / Description | | :---------------- | :--------------------- | :--------------------------------------------------------- | | runtime.name | string | node, bun (More coming soon) | | runtime.version | string | SemVer range (e.g. >=18.0.0, ^20) or Exact (20.11.0) | | os | string | string[] | windows, linux, macos | | packageManager | string | npm, pnpm, yarn, bun | | envFiles | string[] | List of file paths (e.g. ['.env', '.env.local']) | | env | object | Key-value pairs where value is required or optional |

[!NOTE] > Current Limitations: Parity currently supports Node.js and Bun runtimes. Support for Deno, Python, and Go is planned for future updates.

⚡ Features

npx parity fix

[!TIP] > Special Characters: Parity automatically quotes your input to safely handle characters like # or spaces. Enter only the value (do not add your own quotes or inline comments).

custom:
  - name: "Docker Check"
    command: "docker info"
    error: "Docker is not running!"

🤖 CI/CD Integration

Use the --ci flag to treat warnings as errors.

# GitHub Actions Example
- name: Run Parity checks
  run: npx parity check --ci

🤝 Contributing & Support

Found a bug? Open an issue.