chocky335
Lead Mobile Engineer · React Native · Swift · Kotlin
Lead Mobile Engineer with 10 years in software engineering, 9 of them in React Native, plus native iOS (Swift) and Android (Kotlin). I lead the mobile team behind Keet at Tether: a peer-to-peer, end-to-end encrypted messenger with 1M+ installs on Google Play, built on the Bare runtime by Holepunch. Before that: the Bitfinex trading app (500K+ installs) and a crypto-wallet MVP for the P2PB2B exchange with live WebSocket feeds and biometric sign-in. Hands-on with Expo Modules, native modules in Swift and Kotlin, secure storage, CI with end-to-end tests on real devices. Open source: merged pull requests in Biome and Expo, author of react-native-swipeable-actions. Looking for lead or staff mobile roles at wallets, exchanges and messengers: remote (EET, UTC+2), contract or full-time.
Experience: 10 years
Yearly salary: $160,000
Hourly rate: $80
Nationality: 🇺🇦 Ukraine
Residency: 🇺🇦 Ukraine
Experience
Lead Software Engineer, Mobile
Tether (Keet by Holepunch) 2024 - 2026
Lead the mobile team for Keet, a P2P end-to-end encrypted messenger (React Native plus native iOS and Android; 1M+ installs, 4.2 stars on Google Play, 4.5 on the App Store). Own release planning and priorities, hands-on in code and reviews. Set up automated end-to-end runs on real iOS and Android devices in CI, migrated the build runners, automated the release steps, introduced AI-assisted code review with repository-level checks, and moved linting to Biome with three merged upstream PRs. Senior Mobile Engineer from Sep 2024, Lead from Oct 2025.
Senior Mobile Engineer
Bitfinex 2023 - 2024
Trading app of one of the longest-running crypto exchanges (React Native, iOS and Android; 500K+ installs on Google Play). Built the React Native CI/CD on GitHub Actions with multiple environments, brought heavy bi-directional multimedia lists to 60 fps with an event-driven data flow, and built native modules with the Expo Modules API in Swift and Kotlin for video and asset processing.
React Native Developer (freelance, part-time)
P2PB2B 2021 - 2022
Built a crypto-wallet MVP from scratch for the P2PB2B exchange: application architecture, pixel-perfect UI, live lists that handle hundreds of WebSocket events per minute without UI freezes, biometric sign-in, and migration of business logic from the web app.
Lead Software Engineer
GlobalLogic 2019 - 2023
Built and led a five-person engineering team in Ukraine: planning, development, testing and delivery for a client product. Interviewed 20+ candidates, hired five engineers and onboarded four. Shaped the backlog with product owners and designers, contributed to the architecture, set up CI/CD, reviewed code and mentored engineers into new technologies.
Senior Software Engineer
AgileEngine 2018 - 2019
Sole developer on a React Native app with 1M+ downloads: full UI redesign, architecture rework, screen performance up to 3x, post-release support.
Mobile Developer
Knipster 2017 - 2018
Built a daily fantasy football app from scratch in a team of five: React Native UI with Elm business logic, Zendesk feedback loop with hundreds of beta testers.
Skills
android
architecture
blockchain
ci-cd
crypto
fintech
ios
kotlin
mobile
react
react-native
security
swift
typescript
web3
web3js
english
ukrainian