littlecastrum

Coordinated a team of three developers to build a real-time traffic monitoring system processing 1080p video from 50 cameras across 5 cities. Owned the Next.js frontend; co-designed the Go video-ingestion pipeline (OpenCV frame analysis, buffered hand-off to NestJS backend).

Led frontend for Boosted Jobs and Ad Credits, Upwork’s core monetization features. Nuxt 3, Vue.js, GraphQL. Upwork’s SEC 10-K filings cite these as a major driver of Marketplace take-rate growth from 13.8% to 18.0% on $662M revenue. Rebuilt the critical path of an underperforming high-traffic Nuxt 3 conversion funnel, fixing a chain of performance bottlenecks and user-experience (UX) friction. Completion rates doubled. Introduced AI-assisted development at Upwork — integrated GitHub Copilot, Cursor, and Claude Code into continuous-integration/continuous-deployment (CI/CD) pipelines — and raised test coverage from 40% to 90% with a Cypress end-to-end (E2E), Jest, and Vitest strategy the frontend guild still uses.

Shipped drag-and-drop shift scheduling across web (React, TypeScript) and mobile (React Native) with availability management and conflict detection. 30,000+ National Health Service (NHS) workers use it to manage their rotas. Replaced polling across 3 client apps with a GraphQL real-time subscription layer. Live shift availability, no page refresh needed. Redesigned the billing UI and Stripe integration — diagnosed lock-contention issues in the underlying payment system and collaborated on the async queue redesign that cut support tickets by 50%.

Owned the real-time chat UI inside Excite, the game-loading framework powering 8 casino brands (Jackpotjoy, Virgin Games, Monopoly Casino) and tens of millions of players. The platform did £728m in revenue the year I joined and was acquired by Bally’s for $2.7bn later that year. Sustained WebSocket state sync and sub-frame rendering performance under high-concurrency live gaming sessions, all in vanilla JavaScript.

Delivered authentication flows, Stripe integrations (including webhook handling and payment-retry UX), admin dashboards, and CI/CD pipelines across 10+ client engagements in React, TypeScript, Node.js, Ruby on Rails, and Angular 1.5, deployed with Docker on AWS. The first 4.5 years of my career were a bootcamp in ramping up fast on unfamiliar codebases.