I don't just write code. I ship things people install.
Notarized Mac apps. Apps live in the App Store. Storefronts that take real payments. I'm Gero — I build the whole thing, from the Rust binary to the Stripe webhook, and then I put my name on the download button.
EyeGuide AI
Point your phone at whatever you are fixing — a dripping tap, a car engine, a dishwasher throwing an error code — and EyeGuide watches through the camera, answers out loud and draws a marker on the exact part you should touch next. Ask mode sends one frame per question and tracks the object with Vision, so the marker stays on it as you move the phone. Live mode streams camera and voice over a WebSocket for hands-free coaching while both hands stay on the job. Native SwiftUI on Gemini, with the API key kept server-side behind a proxy rather than shipped in the app.
Three Mac apps you can install right now
Not demos. Real applications with a Developer ID signature, an Apple notarization ticket and an open repository.
AI Box
A native macOS app that puts agentic chat, a writing studio, local image generation and a real terminal behind one window — then hands you the controls on your phone while the Mac does the work and keeps your API keys.
Skribble
A paint app in the spirit of the one everybody already knows — shapes, arrows, a fill bucket, text — with a second mode that turns the whole screen into the canvas, so you can circle the thing you are talking about instead of describing where it is.
Gridly
A Mac spreadsheet that opens the .xlsx someone actually sent you — fonts, fills, borders, number formats, merged cells and frozen panes all still where Excel left them — then writes it back out as a real Excel file.
What I actually do
Native Mac apps
Tauri, SwiftUI and Electron — signed, notarized and shipped from a real Developer ID, not a zip with instructions attached.
iOS in the App Store
Swift and React Native apps that made it through review and are live on the store, not screenshots of prototypes.
Commerce that takes money
Storefronts with Stripe checkout, EU and international shipping, admin dashboards and transactional mail that actually sends.
AI that does something
Agentic tooling, generation platforms and analysis backends — wired to real models and real data, with the keys kept where they belong.
The tools I reach for
Got something that needs building properly?
Web, mobile or desktop — from the first commit to a signed binary or a store listing. Tell me what you have in mind.