Available for Remote · Full-time Contract

Rajan Kumar

Senior Frontend Developer · React · React Native · Web3 · 8+ years building production web & mobile apps

Hire Me LinkedIn GitHub
📍 New Delhi, India · Remote 📧 rajankumar.it.msit@gmail.com 📱 +91 7004025870

01. About

Senior frontend developer with 8+ years of experience building production web and mobile applications across React, React Native, and TypeScript. Experienced in Web3/DeFi (Wagmi, Ethers.js, wallet connect, transaction signing) and shipping products from zero to production for iOS, Android, and web platforms.

Proven track record owning features from architecture through App Store/Play Store release in fully remote teams. Strong in scalable architecture, performance optimization, automated testing (Jest, Cypress), and cross-functional collaboration with product, design, backend, and blockchain teams.

02. Core Skills

React React Native TypeScript JavaScript Next.js Node.js Tailwind GraphQL WebSocket TanStack Query Redux Zustand Wagmi Ethers.js Wallet Connect DeFi Web3 Jest Cypress Sentry CI/CD Figma Firebase Cursor Claude Code OpenAI API LLM Integration AI-Assisted Development

03. Work Experience

Senior React Native Developer
YP Club · Remote (Dubai) · ypclub.com
Aug 2025 – May 2026
  • Owned end-to-end development of a production React Native membership app (iOS & Android) from architecture to App Store/Play Store releases.
  • Designed scalable mobile architecture with React Navigation, TanStack Query, Zustand, and MMKV for offline-friendly data.
  • Built wallet/payment flows, Apple Pay native module, Telr SDK, and secure asset handling.
  • Implemented real-time messaging via GraphQL subscriptions and WebSocket; added biometric auth via Keychain.
  • Optimized rendering, list virtualization, and bundle size; resolved production issues using Sentry across dev/staging/production.
  • Coordinated with product, design, and backend teams to gather requirements and deliver high-impact features on tight release cycles.
Lead Frontend Developer
Sperax · Remote (USA) · sperax.io
Sep 2022 – Jul 2025
  • Led design and implementation of new features for SPERAX, improving user experience, functionality, and overall product quality.
  • Optimized code quality and performance using modern React patterns, Wagmi, and Ethers.js for wallet connect, staking, yield, and on-chain interactions.
  • Collaborated with UX/UI designers to create responsive, visually appealing DeFi interfaces across web platforms.
  • Conducted code reviews and mentored junior developers to ensure coding standards and faster release velocity.
  • Used performance monitoring tools (Lighthouse, Sentry) to identify bottlenecks and improve application efficiency.
  • Coordinated with cross-functional teams to gather requirements and deliver high-impact blockchain and protocol solutions.
  • Implemented automated testing (Jest, Cypress), maintained documentation, and improved SEO with Lighthouse audits.
Associate Frontend Developer
Rapid Innovation · Noida, India · rapidinnovation.io
Jun 2018 – Aug 2022
  • Developed 5–6 full-fledged products from scratch with pixel-perfect UI across gaming, DeFi, NFT, finance, and education domains.
  • Translated Figma and Adobe XD designs into responsive, interactive, production-ready React web interfaces.
  • Built high-quality frontend features with strong focus on performance, usability, and maintainable component architecture.
  • Wrote Jest unit tests for component-level reliability and Cypress E2E tests to validate critical user journeys before release.
  • Partnered with cross-functional teams on tight launch timelines from discovery through production deployment.

04. Key Projects

YP Club

React Native · TypeScript · GraphQL

Production membership app with real-time chat, wallet/payments, biometrics, and iOS/Android store releases.

ypclub.com →

Sperax

DeFi · Web3 · React · Wagmi

DeFi protocol frontend with wallet connect, on-chain transactions, staking UI, and yield interactions.

sperax.io →

PICO Wallet

DeFi · Web3 · React

Non-custodial crypto wallet for asset management, transaction signing, and secure Web3 interactions.

KIMO AI

E-learning · React · TypeScript · AI

AI-powered e-learning platform with interactive courses, personalized learning paths, and progress tracking.

GitHub →

Chaquen

Gaming · Web3 · Blockchain

Blockchain gaming platform with wallet integration, on-chain interactions, and interactive gameplay UI.

Owens NFT Marketplace

NFT · Web3 · React

NFT marketplace for minting, listing, buying, and selling digital assets with wallet connect and smart-contract integration.

Shontelle NFT Auction

NFT · Web3 · Auctions

NFT auction marketplace with bidding flows, wallet connectivity, and real-time auction state management.

Blokument

Online Signature · Web3

Web3 document signing platform enabling secure digital signatures and blockchain-backed verification.

Dispatch

Messaging · Web3 · Blockchain

Decentralized messaging app with wallet-based identity and secure on-chain communication flows.

BizPilot

Finance · Taxation · React

Finance and taxation platform with dashboards, reporting workflows, and business management tools.

CareerGig

Jobs Platform · React · Node.js

Job marketplace connecting employers and candidates with search, profiles, and application management.

Swellnet App

Surf Forecasts · React Native

Mobile app for surf cams, forecasts, and location-based surf condition tracking.

swellnet.com/app →

05. Open Source

react-native-web3-kit

Web3 utilities for React Native wallets — addresses, chains, ETH/gwei helpers.

npm →

react-native-fetch-kit

Resilient fetch utilities — timeouts, retries, typed JSON, and useFetch hook.

npm →

06. Contact

Education

B.Tech — MSIT, New Delhi
2014 – 2018
Software Engineering, Data Structures, Web Technologies

Get in Touch

Languages: English (Professional) · Hindi (Native)
Soft Skills: Ownership · Mentoring · Remote Collaboration

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