Backend engineering, web3, and app development. Based in Zürich.
What we do
Backend engineering
15 years across distributed systems, API design, and infrastructure. TypeScript / Node.js, Python, Java, with PostgreSQL, GraphQL, data pipelines, and AWS. Available as a senior freelance hire or fractional tech lead, from architecture through to production and on-call.
Web3
DeFi protocol backends in production since 2022, across multiple chains. On-chain indexing, subgraphs, RPC infrastructure, Solidity tooling, and security monitoring (Hypernative, bug bounty programs).
App development
End-to-end product work: native mobile, web, and the servers behind them, from first sketch to the store and production. React Native and Expo, Kotlin, Next.js, with Node and PostgreSQL underneath. Shipped, not just shipped-to-staging.
Recent work
A lean ordering app for club festivals, school events, market stalls, and pop-ups. Orders, kitchen, counter, on any tablet or phone.
zack.eventsAn open-source app for small livestock farms: herd records, health, breeding, and the day-to-day tasks that keep a farm running, on mobile and web.
coltivio.chA workshop and scheduling tool for a coffee-equipment repair shop. Customers, orders, and pickups organised around the day's capacity.
A pocket catalog for coffee bags: photograph the label, pull out the details, and keep the whole collection on your phone.
A personal training dashboard that turns raw activity files from a sports watch into per-workout stats and charts.