Nguyen O.

Senior full stack developer and backend engineer working in Node.js, NestJS, Next.js, PostgreSQL and AWS. Most recently Head of Engineering, now Fractional CTO, for a HIPAA telehealth SaaS serving 100K+ patients.

I work with founders, CTOs and product teams on SaaS products where the technical decisions matter as much as the code: MVP launches, product rebuilds, backend systems, database performance, cloud infrastructure and production issues.

$400K+ earned on Upwork | Top Rated Plus | 100% Job Success | 7,700+ hours | AWS Certified Solutions Architect and Developer

I'm usually brought into projects where the technical work has moved beyond simple feature development.

🔹 Maybe the MVP needs to become a production-ready SaaS platform.
🔹 Maybe the backend is getting harder to maintain.
🔹 Maybe PostgreSQL queries are slowing down as usage grows.
🔹 Maybe background jobs, webhooks, queues or integrations are becoming unreliable.

Or maybe you're about to spend three months building something and want a senior engineer to challenge the architecture before the expensive mistakes happen.

That's the kind of work I enjoy.

What I Can Help You With

🔹 SaaS and MVP development, from architecture to production
🔹 Full-stack development with Next.js, React, TypeScript and Node.js
🔹 Backend systems with NestJS, FastAPI, Django and REST APIs
🔹 PostgreSQL database architecture, migrations and performance tuning
🔹 Redis caching, queues, pub/sub and background processing
🔹 Authentication, permissions, webhooks, integrations and business logic
🔹 AWS architecture, deployments, production environments and reliability
🔹 Existing codebase audits, refactoring, debugging and technical cleanup
🔹 Architecture planning before a new product or major rebuild
🔹 Technical ownership when a founder needs someone who can see the whole system
🔹 AI features in production SaaS on AWS: LLM integration, RAG, AI agents and async AI pipelines
🔹 Healthcare SaaS: HIPAA-aware architecture, PHI handling on AWS, provider and pharmacy integrations

My Core Tech Stack

🔹 Frontend: Next.js, React, TypeScript, Tailwind CSS
🔹 Backend: Node.js, NestJS, Python, Django, FastAPI
🔹 Database & Data Layer: PostgreSQL, Redis, MongoDB, Prisma, Drizzle 🔹 Cloud & Infrastructure: AWS, Vercel, Supabase, Neon, Railway, Render 🔹 Architecture: REST APIs, microservices, event-driven systems, webhooks, queues, background jobs, authentication, role-based permissions 🔹 AI: OpenAI API, LangChain, LangGraph, Vercel AI SDK, RAG pipelines. Preparing for AWS Certified Generative AI Developer - Professional (exam Oct/Nov 2026)