I just reverse-engineered Apple AirDrop with Opus 5.5 to send files between my Mac & Windows PC this is insane... drag a file onto the other computer → hop. it's there. no cloud. no account. no cable. → hop-drop.vercel.app here's the build step by step: • step 1 → open Claude Code on Opus 5.5 in an empty folder and paste the prompt below • step 2 → Opus picks the stack: one Electron codebase that runs on macOS and Windows • step 3 → discovery: every 1.5 s each computer says "i'm here" over UDP on your local network. the other one pops up on a radar • step 4 → transfer: files stream directly between the two machines. the other side gets Accept / Decline. "always accept" for your own computers • step 5 → before any UI, Opus wrote a test: two fake devices find each other and send a folder + a 3 MB file, byte for byte • step 6 → design: Opus split the work across parallel agents. one rebuilt the iOS 17 NameDrop glow as a WebGL shader, one drew 3 icon concepts and picked the best, one built the download site • step 7 → separate reviewer agents checked every piece. one caught a shader bug that would've rendered black on the Mac. i'm on Windows, i'd never have seen it • step 8 → GitHub Actions builds the .dmg and the .exe on every release. the Mac build runs on Apple hardware in the cloud, not on my PC • step 9 → first launch on the Mac: the icon just bounced in the dock. Opus added a startup log and a fallback that forces the window open. next build opened fine one afternoon. zero lines written by me. drop it on the Mac. it lands on the PC. that's it... find full prompt below ↓ Then read the article on how to reverse-engineer anything with Opus 5.5.