Sunil K.

Full-stack web developer with 7+ years of production experience, building SaaS platforms, CRMs, AI chatbots and e-commerce web and mobile apps with React, Next.js, Node.js, Laravel and Python. I own the whole build - frontend, backend, APIs, database, deployment and AI features - so you get a working product, not a handoff. Top Rated | 100% Job Success | 480+ hours logged on Upwork Recent work: - A multi-tenant SaaS CMS with per-tenant databases, custom domain support, automated SSL via Caddy/Nginx, and self-serve tenant onboarding - architecture through production deployment. - An AI chatbot platform with multiple AI personas, custom conversation flows and admin controls, built in Laravel, Vue.js and Node.js (5-star client review). Other products I've built include a 12-module multi-tenant CRM and support workspace, a crypto trading bot platform (12 exchanges and brokers, 9 risk checks on every order), a flight delay claims platform that checks 5 passenger-rights regulations, a random video and text chat app (WebRTC), an online tutoring and lesson booking platform, a POS system, and R&D tax and grant websites - see my portfolio. What I build - SaaS platforms and custom web applications - multi-tenant SaaS, admin dashboards, client portals, LMS and internal business tools - CRM, HRM, POS and other business management systems - E-commerce web and mobile apps (React Native) - REST APIs and integrations - Stripe and other payment gateways, webhooks, CRM/ERP and shipping integrations, third-party APIs - Authentication and security - JWT/OAuth login, role-based access control, multi-tenant data separation and subscription billing - Fixing and improving existing apps - taking over unfinished or messy codebases, bug fixing, refactoring and performance tuning - AI chatbots and AI features - LLM-powered assistants for customer support, lead qualification, booking and internal knowledge bases, using OpenAI, Claude and Gemini APIs with provider fallback Tech stack Frontend: React, Next.js, Vue.js, TypeScript, Tailwind, Inertia.js Backend: Node.js, Express, NestJS, Laravel, PHP, Django, FastAPI, Flask, Python Mobile: React Native Data & infra: PostgreSQL, MySQL, Redis, Docker, AWS, Nginx, CI/CD AI: OpenAI, Claude & Gemini APIs, chatbots, LLM integrations How I work - One developer owning the full stack, so nothing falls between frontend and backend - Clean, documented code your next developer can actually read - I use Claude Code, Cursor and GitHub Copilot to ship faster, with code still reviewed and tested before release - Replies within a few hours and a clear plan before I start building Tell me what you're trying to ship and I'll tell you how I'd approach it, what it will take, and where the risks are - message me or invite me to your job post.