Andres R.

AI-powered full-stack Engineer who builds AI into your product. 15+ years of experience building software with .NET, React, Azure, AWS, and SQL, now delivering faster with Claude Code and OpenAI Codex, and adding practical AI features that clients actually use. I deliver features in days instead of weeks. Top Rated Plus | 100% Job Success | 5,000+ work hours on Upwork. Pursuing a Master's (MS) in Artificial Intelligence at the University of Colorado Boulder. AI features I add to your software: • Natural-language search (“show me SUVs under $25K with low miles” to real filters and results). • Document and data extraction: invoices, receipts, forms, and emails turned into structured data. • Summaries, classification, and auto-generated content (descriptions, replies, reports). • In-app assistants that help users get things done inside your product. • Built properly: OpenAI and Claude APIs, structured outputs, streaming, cost control, and fallbacks when the AI fails. AI-accelerated development: • Full-stack apps and SaaS built faster using AI coding agents, with every change reviewed by a senior engineer. • Legacy modernization: ASP.NET MVC/WebForms and SQL Server systems moved to modern .NET and React/Next.js, then deployed to the cloud. • Modern deployment: production apps shipped on Vercel, Cloudflare, Supabase, and Neon for fast, low-cost hosting, or on Azure and AWS when you need enterprise scale. • Clean architecture, testing, and CI/CD, so the speed doesn’t create technical debt. Why clients hire me: • Any project size: 1-4 week builds, multi-month projects, and multi-year partnerships. • Proven over the long term: one engagement ran 2,500+ hours over ~11 months with a 5-star review, and one code-review partnership has lasted more than two years. • Comfortable as a hands-on developer or as technical lead of a backend team. • Clear communication, bilingual English/Spanish, working in US time zones. Stack: AI: Claude Code, OpenAI Codex, Anthropic Claude API, OpenAI API. Backend: .NET, C#, ASP.NET Web API, Entity Framework. Frontend: React, Next.js, TypeScript, React Native, ASP.NET MVC/Razor. Cloud & hosting: Azure, AWS, Vercel, Cloudflare (Pages, Workers, R2), Supabase, Docker, GitHub Actions. Databases: PostgreSQL (Neon, Supabase), SQL Server, MySQL, SQLite. Need to ship faster, or want to add AI to your product? Send me what you’re trying to achieve and I’ll reply with a practical plan, usually within a few hours.