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About

Zehao Jiang / AI Engineer & Full-Stack Developer

  • 6+ years of full-stack engineering experience
  • Production LLM / RAG / agent systems
  • AI-powered development for faster delivery and better code quality
  • Reach out for AI features that ship in real products, not demos

Looking for an engineer who can put LLMs into production: RAG, agents, and backend services that stay reliable after launch?

For 6+ years I have built backend systems end to end: APIs, data models, auth, payments, and cloud deployment. Over the last stretch of that work I have focused on wiring Claude and OpenAI into real product flows: retrieval pipelines, multi-turn assistants, and agent-style workflows that call tools and write back to the backend. Primary stack: Java + Python, with PostgreSQL / Redis / Qdrant for data and retrieval. I care about systems that are clean to maintain, cheap enough to run, and ready to scale.

What I can do for you

Claude API · OpenAI · Prompt design

  • Connect Claude or OpenAI into live product workflows (not notebook demos)
  • Design prompts and output contracts your backend can parse and act on
  • Multi-turn dialogue with session state, context windows, and failure handling
  • Guardrails: retries, timeouts, rate limits, logging, and cost control

Embeddings · Qdrant · Retrieval pipelines · Spring Data

  • Design chunking, embedding, and indexing pipelines
  • Store and query vectors in Qdrant (similarity search, metadata filters)
  • Build retrieval → context assembly → generation loops behind REST APIs
  • Cache hot retrieval paths with Redis; tune for latency and answer quality

Tool calling · Event-driven workflows · Backend orchestration

  • Agent-style flows: model decides → backend tools run → results return to the model
  • Hook LLM steps into queues, webhooks, and scheduled jobs
  • Automations that touch your DB, payments, notifications, or third-party APIs
  • Keep agent logic testable and observable inside a normal Spring service layer

Java · Spring Boot · Spring MVC · Spring Security · JWT

  • Design and build RESTful APIs from scratch
  • Authentication and authorization (JWT, Spring Security, role-based access)
  • Business logic that stays clean, testable, and maintainable

PostgreSQL · MySQL · Redis · Docker · Nginx · CI/CD

  • Schema design, migrations, complex queries, performance work
  • Production setup on DigitalOcean: Docker, Nginx, SSL, CI/CD
  • Stripe subscriptions and webhooks when billing sits next to AI features

Vue 3 · Nuxt · TypeScript · Tailwind CSS

  • Work alongside frontend teams or handle supporting frontend work independently
  • Define API contracts, handle CORS, integrate backend services end to end

I communicate clearly, deliver on schedule, and am comfortable working independently from requirements through to deployment. Feel free to reach out with your project.

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