Daniel H.

Senior Flutter developer and mobile app developer with 10+ years building iOS and Android apps. I take over apps that are stuck, half-built or generated with AI tools, fix what's broken and ship them to the App Store and Google Play. Flutter, native iOS and Android, and the Supabase, Firebase or Next.js backend behind them. What founders hire me for • Finish and launch an app someone else started. I read your codebase, tell you what to keep, and ship to the stores. • Audit before you spend. A written review of architecture, security (auth, Supabase RLS, exposed keys) and tests, with a prioritised fix list and an estimate. Fixed price. • Fix apps built with Lovable, FlutterFlow, Cursor or Claude. I build with AI agents (Claude Code, Codex, Cursor) every day, so I know where generated code cuts corners and how to put tests around it. • AI features that survive real users. LLM analysis pipelines, assistants and semantic search with pgvector, with validation, retries and fallbacks for when the model returns something broken. Proof • Lead developer on a property inspection platform: Flutter app, Next.js and Supabase portal, and the Gemini analysis pipeline. Designed the fix when 1 to 3% of model responses came back without findings and broke reports. Closed 15 Supabase RLS security issues. Set up automated end-to-end, smoke and stress testing so regressions get caught before release, not by users. • iBOOD: led the move from separate native iOS and Android apps to one Flutter app. Owned the test pipeline and code review, mentored a junior. • Senior Flutter engineer at Formitable (now Zenchef). Flutter work for Simyo. • Rebuilt a sports planning PWA as a native Flutter app. Built a Bluetooth app for a sports hardware company. • Set up a non-technical founding team to make their own app changes safely with Claude Code. Top Rated Plus, 100% Job Success, $70K+ earned on Upwork. Based in the Netherlands, working with startups and scale-ups in and outside Europe.