CALVIN JOHNSON

I'm a senior full-stack engineer with 9+ years of experience building production AI-integrated web, mobile, and trading systems — entirely solo. My output spans 27+ shipped projects: a production travel content platform (Live Your Life) with custom CMS, multi-program affiliate analytics, and Claude API integration; a reinforcement-learning trading platform (SpartusTradeAI) with Soft Actor-Critic agents and live MetaTrader 5 broker integration; an IoT-driven AgTech platform for full-value-chain operations in Ghana; and a published open-source PyPI package (MetaTrader MCP Server) bridging MetaTrader 5 to Claude and ChatGPT via Model Context Protocol. My day-to-day stack is Next.js 15/16, React 19, React Native (Expo), TypeScript, and Python (FastAPI, PyTorch). I integrate Claude, OpenAI, and Gemini into shipped products and have deep experience in reinforcement learning, IoT (ESP32 / LoRa / Zigbee), real-time systems, geospatial visualisation (Cesium, Leaflet, Three.js), and quantitative trading infrastructure. Looking for senior remote contract, part-time (4-day week), or fractional engineering roles with AI-forward teams. UK-based, comfortable across European and US Eastern time-zone overlap. Available immediately, IR35-aware, can invoice via UK Ltd. I thrive in async-first teams where ownership and shipping are valued over standups, and I'm equally happy embedded in a small product team or operating as a fractional technical lead.