Senior Mobile Engineer

Skills

About the Role

You will own and optimize the mobile layer that delivers hyper-responsive trading experiences on phones. You will implement and maintain a real-time data layer in TypeScript with offline caching and graceful reconnection. You will bridge native modules and implement Swift/SwiftUI or Kotlin components when performance demands it. You will define payload and back-pressure strategies with backend engineers, instrument Sentry and performance metrics, surface KPIs in Grafana, and participate in on-call rotations. You will profile and optimize CPU, memory and JS-thread contention and collaborate with design to finesse micro-interactions that sustain native-feeling 60 FPS experiences.

Requirements

• 4+ years crafting production React Native apps in TypeScript, including achieving 60 FPS on complex lists and charts
• Deep understanding of WebSocket and SSE performance tuning on mobile (heartbeats, batching, incremental JSON, back-pressure)
• Experience with Redux Toolkit Query or equivalent real-time data fetching libraries
• Familiarity with native iOS and Android bridges and willingness to use Swift, SwiftUI or Kotlin when required
• Experience profiling CPU, memory and JS-thread contention with Flipper, Xcode Instruments or Android Studio
• Bias toward shipping measurable improvements frequently and iterating based on user feedback

Responsibilities

• Build and optimize React Native screens that stream order-book deltas, PnL and clan leaderboards over WebSockets within sub-100 ms budgets
• Implement a robust real-time data layer in TypeScript with offline caching and graceful reconnection logic
• Bridge native modules and expose SwiftUI or UIKit components to React Native on iOS and equivalent components on Android when required
• Define gRPC and JSON payloads and back-pressure strategies with backend engineers to keep mobile sockets thin and dependable
• Instrument Sentry and performance metrics, surface KPIs in Grafana, and participate in on-call rotations for the mobile stack
• Collaborate with design to finesse micro-interactions and ensure native-feeling 60 FPS experiences
• Profile and optimize CPU, memory and JS-thread contention using Flipper, Xcode Instruments or Android Studio