СJ Apps

We’re looking for a Senior React/Next.js Engineer to join us on a part-time basis and build high-quality mobile-first web applications for our gaming and AI ecosystem.

All development is in mobile web, optimized for Instagram/TikTok WebView, Safari, and in-app browsers.

This is a role for someone who deeply understands modern frontend architecture, performance, and edge cases of mobile browsers.

What you’ll work on

• Building mobile-first apps in Next.js (App Router, RSC).
• Adaptive UI that behaves perfectly in WebView environments (IG/TikTok/Facebook).
• Creating premium UI with smooth animations (Framer Motion, CSS transitions, Lottie).
• Payment flows: Stripe, Paddle, Apple Pay JS, handling tokens, redirects, webhooks coordination.
• API integrations with proper error handling, retries, caching layers, optimistic updates.
• Handling URL parameters, click IDs, attribution tags, and ensuring they survive redirects & WebView limitations.
• Deep debugging of mobile browser issues:

• soft keyboard pushing layout
• safe-area insets
• viewport resizing
• Safari auto-stripping parameters
• WebView navigation quirks
  • Implementing analytics events, custom tracking, deep linking.
   

Requirements (Senior)

• 5+ years React, and solid production experience with Next.js (App Router required).
• Strong understanding of SSR, RSC, ISR, edge runtime, caching strategies.
• Excellent adaptive/mobile layout skills — pixel-perfect on iOS Safari & WebViews.
• Proven experience integrating payment systems (Stripe/Paddle/Apple Pay).
• Deep understanding of mobile WebView limitations and how to bypass them.
• Strong async logic: hooks, SWR/React Query, fetch wrappers, error boundaries.
• Ability to design clean architecture and reusable components.
• High attention to detail and ability to deliver polished UI fast.

Nice to have

• Experience with State machines (XState) or advanced state management.
• Understanding of analytics pipelines, event tracking, attribution.
• Experience with CSP, security headers, anti-abuse techniques.
• Performance profiling (React DevTools, Lighthouse, Web Vitals).
 

What we offer

• Flexible part-time load (ongoing collaboration).
• Fast decision-making, no bureaucracy.
• Work on high-growth mobile gaming & AI products.
• Ownership of features end-to-end.

Salary in job for part-time!

Description
 

We’re looking for a Senior React / React Native Developer (part-time) to help us build high-performance mobile web apps for our subscription-based gaming platform.
You’ll work on fast, polished, mobile-optimized interfaces that run inside Instagram WebView, Safari, and Chrome, with deep integration into Apple Pay SDK, analytics, and custom API flows.

What you will do

• Develop and maintain mobile-first React/React Native web apps with smooth animations and modern UI.
• Integrate Apple Pay SDK, handle payment tokens, confirmations, fallbacks, and custom web-payment flows.
• Connect and optimize backend APIs (REST/JSON), manage state, handle errors, and ensure stability at scale.
• Implement event tracking and analytics for Facebook Ads, TikTok Ads, AppsFlyer, and internal dashboards.
• Build web2app funnels, onboarding flows, paywalls, subscription logic, and retention-driven UI.
• Optimize performance on low-end and high-end devices, reduce bundle size, improve loading speed, and polish transitions.
• Work closely with design to deliver smooth animations and pixel-perfect mobile layouts.
 

Requirements

• 3–5+ years of experience with React / React Native.
• Strong JavaScript/TypeScript fundamentals.
• Confident in Apple Pay SDK, payment integrations, and secure client-side payment flows.
• Experience with analytics integrations: Facebook Ads events, TikTok Ads events, UTM/ClickID tracking, deep links.
• Excellent understanding of mobile browser behavior, especially Instagram WebView & Safari quirks.
• Experience with animations (Framer Motion, Reanimated, Lottie).
• Ability to write clean, optimized, maintainable code.
• Strong debugging and performance-tuning skills.
 

We offer

• Part-time, flexible schedule.
• High-speed product environment with short cycles and direct impact.
• Work on visually rich, animation-heavy mobile web apps.
• A team that values clean code, creativity, and autonomy.