Full-Stack Developer for AI Travel Concierge

We’re Journi, a small startup, AI-powered travel concierge, currently available as a web app. We’re looking for an experienced full-stack engineer for 20 to 25 hours a week on a rolling contract to keep building and improving our existing web app. You’ll work alongside two junior developers. We want someone who can own technical decisions, review code, and ship features end to end. Our stack Frontend: React and TypeScript, hosted on Vercel Backend: Supabase (Postgres, Auth, Row Level Security, migrations) and Deno edge functions AI: OpenAI API for trip generation and refinement, prompt design, Zod validation Integrations: Google Places and Maps APIs, Stripe subscriptions, PostHog analytics, travel affiliate APIs GitHub with separate staging and production environments What you’ll do -Add new features and improvements to our existing web app -Improve Travel DNA personalisation and the quality of the AI-generated itineraries -Review pull requests and guide our junior developers -Look after release safety: staging, migrations, backups and monitoring -Keep API and AI costs under control About you -5+ years of professional full-stack experience, with production React, TypeScript and Postgres -Hands-on with Supabase or a similar Postgres backend, including migrations and Row Level Security -Has shipped LLM features to real users, not just prototypes -Uses AI coding tools (Claude Code, Cursor or similar) every day, with good judgement about reviewing what they produce -Understands GDPR and handling personal data -Based in the EU or UK, -Travel tech experience is a plus To apply, tell us about one LLM feature you’ve shipped to production and the hardest problem you hit with it.