Paja A.

I help businesses build, improve, and scale SaaS products — from launching new platforms to fixing complex applications that need experienced technical leadership. Whether you're building a SaaS product from scratch, struggling with an existing codebase, scaling a growing platform, or turning an AI-generated MVP into production-ready software, I can take ownership of the architecture, development, integrations, and infrastructure. I'm a Senior Full-Stack / SaaS Engineer with 18+ years of software development experience, specializing in React, Next.js, TypeScript, Node.js, Python, PostgreSQL, Supabase, AWS, and AI integrations. I work with startups, SaaS companies, and established businesses that need someone who can understand the bigger picture, make sound technical decisions, and deliver reliable software without constant supervision. ### SaaS & Full-Stack Development I design and develop complete SaaS platforms, web applications, customer portals, dashboards, and internal business tools. My work includes: - Multi-tenant SaaS architecture and scalable application design - React, Next.js, TypeScript, and modern frontend development - Node.js, Python, FastAPI, and backend services - PostgreSQL, Supabase, database design, and optimization - Authentication, authorization, RBAC, and user management - Stripe payments, subscriptions, and billing integrations - REST APIs, GraphQL, WebSockets, and third-party integrations - AWS, Docker, CI/CD, deployment, and monitoring I can work across the entire system, connecting frontend, backend, databases, and infrastructure into a reliable production application. ### Existing SaaS, Refactoring & Technical Ownership Already have an application that's becoming difficult to maintain, slow to develop, or unreliable? I regularly work with existing codebases that need experienced engineering attention, whether that's improving architecture, resolving performance issues, reducing technical debt, fixing integrations, or preparing the platform for growth. I focus on understanding the system, identifying the actual problems, and improving what already works rather than recommending unnecessary rewrites. I can also step into a senior engineering or technical lead role, take ownership of development, review architectural decisions, and help move a product forward. ### AI Applications & AI-Built Products I build AI-powered applications and integrate AI into existing SaaS products using OpenAI, Claude, LLM APIs, AI agents, MCP, RAG, and workflow automation. I also help businesses turn applications built with Cursor, Claude Code, Lovable, Bolt, and other AI-assisted tools into production-ready software. That means strengthening architecture, authentication, database design, security, API integrations, error handling, testing, monitoring, and scalability while preserving the speed of AI-assisted development. ### Backend, APIs & Cloud Infrastructure Beyond frontend development, I work extensively with backend systems, databases, cloud infrastructure, and integrations. This includes Node.js, Python, FastAPI, Django, PostgreSQL, Supabase, AWS, Azure, Docker, CI/CD, payment systems, OAuth, webhooks, background processing, and production troubleshooting. When a problem involves multiple parts of an application, I can investigate and resolve it across the stack rather than treating each component in isolation. ### How I Work I approach projects by first understanding the product, its users, the existing architecture, and the business goals. From there, I focus on practical technical decisions, maintainable code, clear communication, and delivering software that works reliably in production. I can work independently, collaborate with an existing engineering team, or take technical ownership of a product from planning through deployment. If you're building a SaaS platform, improving an existing application, integrating AI, or looking for an experienced engineer to take ownership of a complex project, send me a message with what you're working on and what you need to achieve.