GitHub Copilot: At Least It Won't Surprise You
Copilot costs $10/month individual or $19/month for business. That's it. No usage tracking, no "effort algorithms", no bullshit surprise billing like Replit's disaster. Your bill is the same whether you write hello world or refactor your entire React app.
Installation is the usual VS Code extension dance - install from marketplace, authenticate with GitHub, done. Your keybindings don't break, your theme stays intact, and it doesn't hijack your IDE like some tools cough Cursor cough. The setup guide walks you through the whole process.
The autocomplete is solid for repetitive patterns. Database queries, API calls, unit tests - all the boring shit you don't want to type out. But don't expect it to architect your app or understand complex business logic. It's glorified autocomplete with chat, not an AI architect.
Copilot can't see your project structure beyond open tabs, so forget about smart refactoring across multiple files. GitHub's own docs admit this limitation - it's designed for line-level completion, not system-level understanding.
Real gotcha: Authentication randomly breaks in VS Code 1.82+ on Windows. You'll get "Copilot not authenticated" errors even when you're clearly logged in. The community fix: Sign out completely, clear authentication cache, restart VS Code, sign back in. Takes 5 minutes but happens every few weeks. Microsoft's official troubleshooting basically says the same thing.
Codeium: Actually Free, Not Marketing Free
Codeium's individual tier is legitimately free. Not "free for 30 days" or "free for students only" - actually free forever for personal use. No credit card required, no usage limits, no bullshit. Teams pay $12/user/month, but solo developers get the full feature set at zero cost.
The autocomplete is decent and works in basically every editor that exists - VS Code, IntelliJ, PyCharm, WebStorm, Neovim, Vim, even fucking Sublime Text. Pick your poison, they probably support it.
Auth issues are real: The VS Code extension fails to authenticate about 30% of the time on first install. You'll get a blank chat panel and no suggestions. Stack Overflow is full of this. The fix is annoying but reliable: Ctrl+Shift+P → "Codeium: Authenticate" → restart VS Code. Sometimes takes 2-3 attempts based on user reports.
The chat crashes hard when you paste large code blocks. Like, >200 lines and it just stops responding. Multiple user complaints document this behavior. Their solution? "Try smaller chunks." Thanks, very helpful. Semaphore's detailed review covers more stability issues.
Performance-wise, Codeium runs some processing locally so completions are fast, but it'll eat an extra 200-400MB of RAM depending on your project size. On a 8GB machine with Docker running, this can push you into swap territory. Fair warning.
Cursor: Great When It Doesn't Crash
Cursor is the closest thing to "AI that actually understands your codebase" but it crashes like a motherfucker. I've used it for 6 months and have a love-hate relationship that borders on Stockholm syndrome. You can find it by searching "Cursor AI editor" and prepare for a wild ride.
The agent mode is genuinely impressive when it works. Ask it to "refactor this React component to use hooks" and it'll touch 8 files, update imports, fix prop types, and somehow not break anything. It's the only tool I've used that actually gets component relationships. Their documentation claims it can handle complex codebases, and when it doesn't crash, it delivers.
Windows users beware: Cursor crashes hard on large TypeScript projects. The TypeScript language server constantly crashes when the agent tries to parse complex types. Multiple development blogs document JS/TS crashes, mostly Windows users with TS codebases. The unofficial fix is to exclude node_modules and disable deep TypeScript analysis in settings. Developer guides provide workarounds involving memory tuning and excluding directories.
Memory leaks are real. After 4-5 hours of coding, Cursor will be eating 4GB+ of RAM and responding like molasses. The agent mode starts taking 30+ seconds per request. Solution: restart the app every few hours like it's 2005.
Credit consumption is insane: A single "refactor this component" can burn through 10-15 API calls as it analyzes dependencies. I've seen $50 worth of credits vanish in one afternoon of heavy refactoring. Pricing is around $20/month individual, but you'll blow through the included credits fast if you use the agent mode seriously. Multiple user reports document similar credit burn rates.
The agent also has a habit of touching files you didn't ask it to. Ask it to update one component and it'll randomly modify your tsconfig.json because it "thought you needed stricter types." Always check the git diff before committing. Comprehensive comparisons document similar frustrations. Developer experience articles cover the file modification behavior extensively.
