Juan U.

I build production-ready NextJS apps and AI integrations (OpenAI, Claude, LangChain, vector search, RAG) for startups that need to ship fast without shipping trash. Top Rated Plus · 100% Job Success · 1,800+ hours delivered.

Recent work:
• Pulse — fitness SaaS I co-founded and built. React Native + Node + Postgres, architected to scale from 100 to 10K+ users.
• Spawned — AI-powered app builder with real-time build streaming (Socket IO, Redis, BullMQ, Solana).
• White Rock Millwork, Sembroni, BFL — premium marketing sites built in NextJS 15 with GSAP and Framer Motion.

Where I fit best:
→ Early-stage founders who know what they want and want it shipped
→ Agencies that need NextJS and React overflow capacity
→ Established teams adding AI (OpenAI, Claude, LangChain) to an existing product

Real numbers from past roles (not LinkedIn fluff):
• Reduced error resolution time by 53% on an enterprise AI chatbot (text, voice, image)
• Increased Stripe payment success rate by 40% via checkout refactor
• Cut deployment time from 30 min to under 5 min with GitHub Actions + DigitalOcean CI/CD
• Built a Python microservice (FastAPI, NumPy, Pandas) analyzing millions of poker hands in under 50ms

Tech I use daily:
NextJS (App Router), TypeScript, React, React Native, Tailwind, Framer Motion, GSAP · NodeJS, Express, Python (FastAPI), PostgreSQL, MongoDB, Prisma, Redis, BullMQ · OpenAI API, Claude API, LangChain, AI agents, vector search · Stripe, GoHighLevel, Meta Pixel CAPI, Socket IO · AWS, Docker, Terraform, GitHub Actions, Vercel, DigitalOcean

What clients have said:

"Juan did an excellent job on this task, despite it being in a new area where he had limited prior experience. He quickly got up to speed, demonstrating a remarkable ability to learn and adapt... I was consistently impressed by his strong communication skills and his proactive approach." — Angela Wu, Founder at Komo AI

"Juan is excellent! Very responsive and on-time on deliverables." — Domenica Cheek, CEO at Avanti Creativo

I'm fluent in English and Spanish and respond to messages in under 4 hours. If you send a clear brief, I'll come back with a scoped estimate and — if the job warrants it — a short Loom walking through how I'd build it.