I’m Sang. Over 10+ years in software engineering, I’ve built and maintained web products across backend, frontend, cloud infrastructure, and applied AI — usually where product complexity and technical ownership meet.
I own engineering end to end — from requirements and system design to backend, frontend, deployment, and production support. I’ve been doing this long enough to move quickly through ambiguity and focus on what creates value.
My core background is in PHP and Laravel platforms, modern React applications, Python services, AWS infrastructure, and the practical integration of language models into real products.
When the path is unclear, I make it concrete. That’s usually why I’m hired.
What I do
- Turn complex requirements into clear, buildable systems.
- Move comfortably from backend architecture to product interface.
- Add AI where it creates real leverage, not theatre.
Building knowledge systems
RAG and conversational products that connect language models to trusted business
data. RAG · FastAPI · OpenAI
Engineering agentic workflows
Practical agents with clear boundaries, observable steps, and humans kept in
control. AI Agents · LangGraph · APIs
Shipping full-stack platforms
End-to-end web products with durable architecture, polished interfaces, and
reliable operations. Laravel · React · AWS
Core stack
| Area | Tools |
|---|---|
| Backend | Laravel / PHP, Python / FastAPI, Node.js, PostgreSQL |
| Frontend | React, Next.js, TypeScript, design systems |
| Applied AI | RAG, AI agents, chatbots, OpenAI / Claude, LangChain / LangGraph |
| Infrastructure | AWS, Docker, CI / CD, system design |
Track record
58 jobs completed on Upwork with 100% Job Success and Top Rated status.
Good to know
What kind of work are you open to?
High-ownership full-stack projects, backend architecture, AI-enabled product features, and longer-term technical partnerships. I’m most useful when the problem is real, the requirements are evolving, and reliable delivery matters.
Can you own a product end to end?
Yes. I can move from requirements and architecture through backend, frontend, infrastructure, deployment, and production support. I also work comfortably inside an existing team when the scope needs a focused senior engineer.
How do you communicate with remote clients?
Async by default, with concise written updates, visible decisions, and early flags for risks or trade-offs. Calls are useful when they unblock work; progress should not depend on meetings.
How do you approach AI features?
As product engineering, not a demo. That means grounding, evaluation, failure handling, cost awareness, security, and clear limits around what the model should and should not decide.
Contact
Based in Ho Chi Minh City, Vietnam. The fastest way to reach me is Upwork, or sangcnt@gmail.com.