Rajendra Kumar

Senior full-stack developer with 5 years of experience building production web and mobile apps. I help startups and businesses turn ideas into fast, reliable products that real users rely on.

What I can build for you:

Web apps in React.js and Next.js: marketplaces, e-commerce stores, admin dashboards, booking and reporting tools
Cross-platform mobile apps in React Native (iOS and Android), including App Store and Google Play publishing
Backend services and REST/GraphQL APIs with Node.js and Express.js, with JWT/session authentication and payment gateway integration
Firebase integration: push notifications, analytics, crash reporting
CI/CD setup and deployment on AWS, GCP, Azure and Vercel
Performance optimization: lazy loading, code splitting, smaller bundles, faster load times
Automated testing with Jest, plus clean, reusable component architecture

Experience that backs it up:

Delivered apps used by 10,000+ monthly active users across automotive, e-commerce, healthcare, social networking and parking management
Shipped a dealer app and web platforms serving 1,000+ active dealers with 99% uptime
Led a team of 5 developers across web, mobile and backend work
Cut deployment time by about 75% with automated pipelines
Improved page load times by 15-25% and raised test coverage on critical features to 90%
Built offline-capable mobile apps with sync, camera and media upload, and map-based booking

Tech stack: JavaScript (ES6+), TypeScript, React, Next.js, React Native, Expo, Redux Toolkit, Zustand, Node.js, Express, Material-UI, Docker, Git, Figma, Postman.

How I work: clear communication, regular progress updates, clean maintainable code and on-time delivery. I can take a project from Figma design or rough idea to launch, or join an existing codebase to fix bugs, add features and speed things up.