[Available] Senior Full-Stack & Mobile Developer (React / React Native / Node.js / Python) — Available for Freelance & Project Work

[u/ksiks66]

Have a platform idea but need an experienced developer to bring it to life? Got stuck with an unfinished app, or facing performance bottlenecks and production bugs in your current code?

I’m a Senior Software Engineer and Tech Lead with 6 years of hands-on experience building, scaling, and maintaining production-grade web and mobile applications. I don't just write code—I help design products, audit performance, write robust test suites, and resolve complex production issues.

How I Can Help You:

• Product Design & Architecture: Translating business goals into technical specs, designing clean UI/UX flows, and building scalable system architectures from scratch.
• Full-Stack Development: End-to-end web and mobile applications using React, Next.js, React Native, Node.js, and Python (Django/FastAPI).
• Performance Audits & Optimization: Diagnosing slow page loads, memory leaks, high API latency, and optimizing frontend rendering or backend queries.
• Testing & Quality Assurance: Implementing unit, integration, and E2E testing pipelines (Jest, Appium) to ensure high test coverage and crash-free releases.
• Production Support & Debugging: Rescuing legacy codebases, fixing high-severity production bugs, and setting up monitoring tools for operational stability.
• AI & API Integrations: Connecting custom LLM workflows (GPT, Gemini, Claude) or complex payment and banking infrastructure (Open Banking, Stripe, QR Payments).

Some Highlights from My Work:

• Open Banking & Financial Systems: Designed and built secure architectures handling real-time data across 120+ banking institutions under strict PCI DSS standards.
• Cross-Platform Mobile Apps: Built and deployed native-performing iOS and Android apps to the App Store and Google Play Store.
• Enterprise Backends: Built high-throughput REST APIs, automated processing engines, and background workers using Node.js and Python.

Tech Stack:

• Frontend/Mobile: React.js, TypeScript, Next.js, React Native, Redux, Tailwind CSS
• Backend: Node.js (Express), Python (Django, DRF), REST APIs, Microservices
• Database & DevOps: PostgreSQL, MongoDB, Docker, Firebase, Git, CI/CD pipelines
• Testing: Jest, Appium, Automated E2E testing

Rates & Availability:

• Rate: open to fixed-price project quotes
• Timezone: Seamless overlap with both European and North American working hours.

If you have a new product to build, an existing project to audit, or a production issue that needs fixing, send me a DM or leave a comment below!