Danny K.

I build AI agents that actually do the job — they use tools, remember context, and run real business workflows end to end. 10+ years in Node.js and TypeScript, 4,000+ hours on Upwork, 96% Job Success, Top Rated. Most "AI developers" ship a chatbot wrapper. I ship systems: solid backend architecture underneath, with OpenAI, LangChain.js, and vector search (Qdrant, Supabase/pgvector) on top. That difference is why my clients keep me for years instead of weeks. WHAT I BUILD - AI agents and RAG systems — connected to your real data, your real tools, with memory and guardrails - Workflow automation — one client's automation build ran 600+ hours and $41K over two years, replacing manual work across their entire content pipeline - Production APIs — REST and GraphQL on Express or NestJS, PostgreSQL, MongoDB, Supabase - Full MVPs, prototype to launch — React, Vue, React Native, Electron - Browser-driven data collection and evidence logging — NestJS + Playwright at scale HOW I WORK I start with your use cases, not your tech stack. We map what the system has to do, then I design the schema and architecture around it, write test cases per use case, and ship module by module so you see progress weekly — not a black box for six weeks. With Cursor and Copilot I move 3–5× faster than traditional development, and I pass that speed on to you rather than billing for it. STACK Backend: Node.js, TypeScript, Express, NestJS AI: OpenAI API, LangChain.js, RAG, MCP, vector databases (Qdrant, pgvector) Frontend: React, Vue, React Native, Electron Data: PostgreSQL, MongoDB, Supabase, Firebase Infrastructure: AWS, GCP, Azure, Docker WHAT CLIENTS SAY "Fantastic dev, good quality TS work and very proactive." "Danny is stellar. Excellent work and I have enjoyed working with him." "Highly skilled, detail-oriented, and proactive in finding solutions." Before Upwork I was a Solution Architect at Oracle and a DevOps engineer at Amdocs, building for AT&T, Comcast, and Vodafone. I've seen what breaks at scale, and I build so it doesn't. Tell me what you're trying to build and I'll tell you honestly whether I'm the right fit — and how I'd approach it.