zitoon is a software engineering studio based in Geneva. We build Android, web and embedded applications using Spec-Driven Development — every feature is written, challenged, then implemented. The resulting code is maintainable, scalable, and documented by design.
Every project follows the same backbone: spec before code, documentation alongside implementation, ship code another developer could pick up tomorrow. Nothing revolutionary — just rigorously maintained.
Every feature, every bug, every change has its document. Short, versioned, precise. Not paperwork — it's the contract between intent and code. Nothing gets coded that hasn't been written first.
Standard architectures, mature stacks, shared conventions. A third-party developer must be able to open the repo and understand it within hours. Software archaeology is not a viable business model.
Separation of concerns, tests where they matter, explicit boundaries between modules. Software lives — it must accept without pain the feature we don't know about yet.
Internet radio streaming with large touch tiles, favourites pages, 40,000+ global stations via Radio Browser API. Media3/ExoPlayer for background playback, MVVM + Repository architecture.
Vertical swipe navigation between files in the same folder, hardware decoding via Media3 ExoPlayer, pure Compose UI, pre-loading of adjacent videos.
Wake-on-LAN, SSH with Ed25519 keys in Android Keystore, multi-source network scanning (ARP Netlink, mDNS, NetBIOS, SSDP/UPnP, SSH banner grab), heuristic OS classification.
All-in-one Raspberry Pi 5 for community libraries and remote schools. Local Wi-Fi hotspot, Moodle, Kolibri (Khan Academy, Wikipedia offline), Koha (ILS with RFID). Power-cut resistant.
Searches option combinations (2–4 legs) on S&P 500 and underlyings, smile profiles with capped losses and large gains at extremes. Vectorised CUDA Black-Scholes pricing, Streamlit interface, Plotly charts.
Real-time conversion across 6 categories: lengths, weights, speeds, temperatures, volumes, areas. Horizontal carousel, combined sections (ft+in, lb+oz), preference persistence. Web + Android via Capacitor.
30-minute time grid, one tap to fill in client + activity. Week view, CSV export, day lock, 100% offline (localStorage), multilingual FR/EN. Zero backend, zero authentication.
Spec-Driven Development is not disguised waterfall. It's a lightweight discipline of formulating every intention before executing it. Each document becomes the working contract between the client, the engineer, and the AI tools assisting production.
Intent, scope, acceptance criteria, technical constraints. One short but precise document per unit of change.
Review: uncovered angles, conflicts with existing code, probable side effects. Questions get closed on paper.
Code follows the spec. AI executes, the engineer validates. Divergences go back into the spec, not into comments.
The spec is versioned alongside the code. A year later, you know why a decision was made — not just what.
The true cost of software is not measured at its first version. It's measured by how easily you add the second, the tenth, or someone else's.— Guiding principle · zitoon