Cross-Platform Compatibility

Table of Contents

• Overview
• When to Use
• Quick Start
• Reference Guides
• Best Practices

Overview

Comprehensive guide to writing code that works seamlessly across Windows, macOS, and Linux. Covers file path handling, environment detection, platform-specific features, and testing strategies.

When to Use

• Building applications for multiple operating systems
• Handling file system operations
• Managing platform-specific dependencies
• Detecting operating system and architecture
• Working with environment variables
• Building cross-platform CLI tools
• Dealing with line endings and character encodings
• Managing platform-specific build processes

Quick Start

Minimal working example:

// ❌ BAD: Hardcoded paths with platform-specific separators
const configPath = "C:\\Users\\user\\config.json"; // Windows only
const dataPath = "/home/user/data.txt"; // Unix only

// ✅ GOOD: Use path module
import path from "path";
import os from "os";

// Platform-independent path construction
const configPath = path.join(os.homedir(), "config", "app.json");
const dataPath = path.join(process.cwd(), "data", "users.txt");

// Resolve relative paths
const absolutePath = path.resolve("./config/settings.json");

// Get path components
const dirname = path.dirname("/path/to/file.txt"); // '/path/to'
const basename = path.basename("/path/to/file.txt"); // 'file.txt'
const extname = path.extname("/path/to/file.txt"); // '.txt'

// Normalize paths (handle .. and .)
const normalized = path.normalize("/path/to/../file.txt"); // '/path/file.txt'

Reference Guides

Detailed implementations in the references/ directory:

Best Practices

✅ DO

• Use path.join() or path.resolve() for paths
• Use os.EOL for line endings
• Detect platform at runtime when needed
• Test on all target platforms
• Use optionalDependencies for platform-specific modules
• Handle file permissions gracefully
• Use shell escaping for user input
• Normalize line endings in text files
• Use UTF-8 encoding by default
• Document platform-specific behavior
• Provide fallbacks for platform-specific features
• Use CI/CD to test on multiple platforms

❌ DON'T

• Hardcode file paths with backslashes or forward slashes
• Assume Unix-only features (signals, permissions, symlinks)
• Ignore Windows-specific quirks (drive letters, UNC paths)
• Use platform-specific commands without fallbacks
• Assume case-sensitive file systems
• Forget about different line endings
• Use platform-specific APIs without checking
• Hardcode environment variable access patterns
• Ignore character encoding issues