Haider A.

Senior Full Stack Developer building SaaS and AI-powered web applications with Next.js, React, Node.js and TypeScript. I help startups build MVPs, improve production apps and integrate reliable AI features. $100K+ earned | 10,000+ Upwork hours | Top Rated | 100% Job Success | 9+ years of experience I work with SaaS founders and product teams that need senior-level ownership across frontend, backend, APIs, databases, integrations and production architecture. WHAT I BUILD • SaaS MVPs and production web applications • Customer portals and admin dashboards • Next.js and React frontends • Node.js APIs and backend services • Authentication, permissions and multi-user systems • PostgreSQL and Supabase applications • Stripe billing and subscriptions • Third-party API integrations • Existing codebase improvements and stabilization • AI features inside SaaS products PRODUCTION EXPERIENCE • Led development on a platform that processed 100,000+ ecommerce orders • Worked on a platform where merchants generated $100M+ in sales in one year • Built and maintained a business platform with 230+ features • Delivered 10,000+ hours of Upwork development work • Recent Next.js + Node.js customer portal with 5-star feedback • Production AI customer-support assistant with 5-star feedback CORE STACK Frontend: Next.js, React, TypeScript Backend: Node.js, Express, REST APIs Database: PostgreSQL, Supabase, MySQL Infrastructure: AWS, Docker, Vercel Integrations: Stripe, QuickBooks, Twilio and third-party APIs AI PRODUCT DEVELOPMENT When AI genuinely improves the product, I can integrate OpenAI, Claude, RAG, document search, tool calling and AI assistants into existing SaaS applications. The focus is not an isolated AI demo. It is building reliable AI functionality inside a production product. I’m equally comfortable building new functionality and taking ownership of an existing codebase that needs debugging, architecture improvements, performance work or new product features. I prefer long-term product development, but I’m happy to start with a clearly scoped first milestone. If you’re building or improving a SaaS product, send me your current stack and the problem you need solved. I’ll tell you how I would approach it.