Husnain Q.

Senior Full Stack JavaScript Engineer with 6+ years building secure web and mobile apps for fintech, payments and SaaS companies, using React, Next.js, Node.js, TypeScript and React Native. I work full-time in fintech, building payment and banking systems that move real money in production. I've also delivered 75+ apps for clients in Canada, the US and Europe through Upwork, Fiverr and Turing, with consistent 5-star feedback and Top Developer status. WHAT I BUILD - Fintech and banking apps: digital wallets, card platforms, KYC onboarding, credit checks, rewards engines - Payment integrations: Stripe, Apple Pay, Interac, payment gateways, payouts, settlement and reconciliation (PCI-DSS compliant) - SaaS platforms: multi-tenant architecture, subscription billing, role-based access, admin dashboards - Mobile apps: React Native, Expo and Flutter for iOS and Android - Real-time systems: WebSockets, live tracking, notifications, dashboards - AI features: AI chatbots and agents, knowledge bases (RAG), OpenAI, Claude and Gemini integrations - API integrations and automation: REST, GraphQL, webhooks, Twilio, Jobber, Buildium, Paychex RECENT WORK - Plastk (plastk.ca), a Canadian credit card and rewards fintech: cardholder portal, KYC onboarding, card and transaction services, points engine, admin and business portals - Payment platform: pay-ins, payouts, merchant wallets, settlement and reconciliation, with a Next.js back office - Multi-tenant hotel SaaS: Next.js, PostgreSQL, Stripe billing and an AI guest-messaging agent - Vehicle logistics platform: React dashboards, Node.js API and a React Native driver app with live GPS tracking TECH STACK Frontend: React, Next.js, TypeScript, Redux, Tailwind CSS Backend: Node.js, NestJS, Express, Go, Python Mobile: React Native, Expo, Flutter Databases: PostgreSQL, MySQL, MongoDB, Redis, Supabase Cloud and DevOps: AWS, Docker, Kafka, CI/CD, microservices HOW I WORK - Clear communication and regular progress updates - Clean, documented code that your team can maintain - Security from day one: authentication, encryption, OWASP best practices - Experience leading architecture decisions and mentoring junior developers, so I fit in solo or with your team Tell me what you're building and I'll reply with how I'd approach it.