React · TypeScript · Node.js · Regulated Domains · 15+ years' commercial experience

I build reliable, well-tested product applications in demanding environments - IoT compliance platforms, data-heavy operational tools, and high-stakes workflows where correctness isn't optional. Deep front-end ownership, cross-stack awareness, and a direct feedback loop with end users.

Currently based in Hertfordshire, UK · Open to remote and hybrid opportunities

🌐 connection.works  ·  💼 linkedin.com/in/sumeetadur

The most significant recent projects:

L8Log - IoT Legionella Compliance Platform · Remote Tech, Nov 2019 – Jan 2026 A regulated Legionella monitoring and compliance system used across the UK. Led all front-end web development: architecture decisions, technology selection, UI/UX implementation, and production deployment.

• Reduced field assessment turnaround time 8× - from ~2 days to ~2 hours - by building a cross-platform React Native (Expo) app from scratch in 5 months
• Established a Playwright E2E testing framework across Development and Staging environments in a regulated context
• Architected an Apollo GraphQL server; subsequently led a considered migration to RTK Query as the architecture matured
• Built interactive data visualisations for high-volume IoT sensor data; integrated Mapbox for geospatial asset tracking

Stack: React · TypeScript · Redux Toolkit / RTK Query · GraphQL / Apollo · React Native (Expo) · Vite · Playwright · ECharts · Mapbox · Ant Design

Bathroom Design Shop · May 2024 – Feb 2025 High-performance marketing site achieving near-perfect Lighthouse scores.

Stack: Astro (SSG) · React · Tailwind CSS · Contentful · Shadcn/UI

→ View portfolio

const stack = {
  core:     ['React', 'TypeScript', 'JavaScript (ES6+)'],
  backend:  ['Node.js', 'NestJS', 'PostgreSQL', 'Prisma'],   // actively expanding
  styling:  ['Tailwind CSS', 'SCSS', 'Styled Components'],
  data:     ['RTK Query', 'Redux Toolkit', 'GraphQL / Apollo', 'REST'],
  testing:  ['Playwright (E2E)', 'Jest', 'React Testing Library'],
  cms:      ['Contentful', 'Supabase', 'Astro'],
  mobile:   ['React Native (Expo)'],
  tooling:  ['Vite', 'GitHub Actions', 'Netlify', 'Vercel'],
  cloud:    ['Azure (foundations - actively expanding)', 'AWS (prior experience)'],
  ai:       ['Windsurf (AI-assisted development)'],
} as const

• NestJS + PostgreSQL - closing the gap from front-end-strong to full product engineer ownership of the backend
• Azure - foundations in place, working toward AZ-204
• Python / FastAPI - for AI/ML integration layers
• RAG patterns with pgvector - semantic search and document Q&A in compliance contexts

• I keep a direct feedback loop with end users - session recordings, observed behaviour, not just ticket descriptions
• I treat E2E testing and performance as product features, not afterthoughts
• I've led architecture decisions across the full lifecycle: from technology selection through to production deployment in regulated environments
• I use AI tooling (Windsurf) to accelerate migrations and scaffolding - freeing up attention for the decisions that actually require judgement
• I care as much about how something is built as what is built

If you're building something in fintech, healthtech, legaltech, or any domain where reliability and correctness genuinely matter, I'd like to hear about it.

📬 sumeet@connection.works