01
Sep. 2025 — PresentSelana
Software Engineer, Part-time — Dutch electric scooter startup / Remote
- Main engineer on a mobile app that is in production with real riders on it, carrying features the whole way down — from the screens people touch to the Postgres schema and edge functions holding them up.
- Designed the multi-tenant permission model — owner, dealer and admin roles, shared vehicles, fleet groups — and enforced it in the database itself with row-level security, auditing privileged actions and pinning the rules down with database test suites that run on every CI build.
- Shipped subscription billing over two rails at once, Mollie recurring payments and Apple in-app purchase. After tracing a double-charge in production I made webhook handling idempotent and taught entitlement reconciliation to fail closed rather than guess.
- Wired in a real-time AI voice support agent (ElevenLabs over LiveKit WebRTC), lazy-loaded and gated on the native module actually being there, so older clients fall back to email support instead of crashing.
- Built the team's setup for working with coding agents: a repo-local skill library that writes down our release, backend-compatibility and code-review procedures, shared across Claude Code and Codex — including a checker that proves a refactor changed nothing but comments.
React Native / Expo / TypeScript / Supabase / PostgreSQL / LiveKit