Valery M.

$4M+ earned on Upwork. 27+ years, 600+ projects, and platforms serving 20M+ users. I build production-grade SaaS, CRM, ERP, marketplaces, automation & AI systems with PHP, React, Python and modern cloud architecture - built to last, not patched together. Senior Full Stack Developer leading a veteran Full Stack Development team for production-ready SaaS platforms, web applications, CRM, ERP, Marketplace Platforms, automation, and AI-powered applications. We work across full-stack development, web development, web application development, modern web products, B2B SaaS, SaaS applications, production SaaS, web and mobile products, and existing production systems. Results: - 100+ SaaS and CRM platforms launched from scratch - 300+ automation tools built - 150+ POS, Web-to-Print, and location-aware applications delivered - platforms serving 20M+ users with 99.99% uptime - ERP Systems reducing operational overhead by 40%+ - web automation saving 1,000+ hours per month per client Our stack includes Laravel, PHP; Python, Django; React, Next.js; React / Next.js; Next.js, React; React, TypeScript; Next.js, TypeScript; React, Node.js; Node.js, Express.js; PostgreSQL, MySQL; MongoDB, PostgreSQL; AWS, Docker; AWS, Vercel; Tailwind CSS; Redis; GCP; GraphQL; React Native; HTML, CSS; and Node.js, Python. Frontend: React, Next.js, TypeScript, App Router, Tailwind CSS, responsive web interfaces, and modern frontend tooling. Backend: Node.js, Express.js, Python, PHP. Our backend development covers backend services across frontend, backend, APIs, databases, data sources, background jobs, frontend and backend systems, front-end and back-end product layers, relational database environments, and relational databases. We handle API Development, API development, REST APIs, REST API, API Integration, API integrations, API design, GraphQL APIs, third-party integrations, third-party APIs, APIs and third-party integrations, AI APIs, LLM APIs, Authentication and authorization, Secure authentication, role-based access, billing engines, reporting pipelines, and workflow automation. Architecture matters. We design Scalable Architecture, clean architecture, Event-driven architecture, Multi-tenant systems, multi-tenant SaaS, SaaS architecture, application architecture, technical architecture, database architecture, database design, data model planning, architectural decisions, cloud infrastructure, production systems, production applications, production web applications, and Production deployment. We also handle code quality, code reviews, Automated testing, CI/CD pipelines, GitHub Actions, GitHub repository workflows, and ongoing maintenance. We regularly take over an existing codebase, existing code, existing architecture, and existing production systems where the source code already supports active users. We diagnose production issues, stabilize production web applications, modernize a web app without unnecessary rewrites, and improve production systems while preserving working functionality. For AI products, we build AI-powered applications, AI Agents, AI agent systems, AI features, AI workflows, RAG systems, LLM Integrations, OpenAI API, AI integration, integrating AI into SaaS products, AI development, modern AI products, AI tools, AI coding, AI coding tools, AI-assisted development, Claude Code, and carefully review AI-generated code before it reaches production. As a Mobile App Developer team, we deliver iOS and Android applications using React Native and native stacks. Our mobile application work includes production mobile applications tightly integrated with scalable backend services. We also work as: - Full Stack Web teams on SaaS Platforms, ERP, CRM, POS, LMS, Marketplace Platforms, fintech, and data platforms - MERN Stack Developer teams using React, Node.js, Express.js, and MongoDB - React/Next.js Developer teams on complex UI platforms - Python full-stack teams on enterprise systems, analytics, and automation - AI Full Stack Developer teams on AI Automation, RAG, OpenAI API, and ML-powered products We handle system architecture, Full Stack Development, application development, DevOps, Cloud DevOps, AWS (EC2, S3, Lambda), Docker, CI/CD, Cloud Deployment, Apache, Nginx, security, monitoring, and long-term maintenance. Whether you need a Full Stack Developer to own a product from idea to production, a SaaS Developer to build or scale a SaaS platform, a Web Developer to extend a system, a React Developer or Next.js Developer to rebuild your frontend, a Node.js Developer or Backend Developer for API Development, or a MERN Stack Developer for a JavaScript product, we bring decades of hands-on experience and production-grade delivery.