GitHub Copilot

GitHub Copilot autocompletes code as you type, powered by OpenAI Codex. It's like autocomplete on steroids — suggests entire functions, test cases, and implementation patterns based on your context. Works across all major languages and integrates directly into VS Code, JetBrains IDEs, and Neovim. The suggestions are often correct enough to accept with minor tweaks.

Best for professional developers who write code daily and understand what the AI is suggesting. It shines for boilerplate code, test generation, and implementing common patterns. Senior engineers use it to speed up the boring parts while focusing mental energy on architecture. Junior developers benefit from seeing implementation examples inline.

Where it struggles: confidently suggests wrong patterns sometimes, doesn't understand your specific business logic without context, and can make you lazy about learning APIs properly. The subscription cost ($10/month) is worth it if you code full-time, questionable if you're a weekend hobbyist. Treat it as a productivity boost, not a replacement for understanding your codebase.