Senior React Native Performance Engineer

Afriex is a pioneering platform that allows its users to send and receive money to anybody around the globe. We use stablecoins to offer the fastest and cheapest remittance service to over 30 countries around the world.

Location: Remote
Company size: 10–100
Posted: 5d ago
Via: Yc

Section II · Premium ProfileMembers only

01Comp band & equity packageLocked
02Seniority & experience requirementsLocked
03Interview process & rubricLocked
04Hiring manager & team contextLocked
05Growth trajectory in this roleLocked
06Offer & decision timelineLocked

Start free trial Sign in

7-day free trial · $25/mo · cancel anytime

Senior React Native Performance Engineer · Afriex

View company profile

Job title: Senior React Native Performance Engineer
Job location: Remote
Job listing URL: https://www.ycombinator.com/companies/afriex/jobs/4VtOnnB-senior-react-native-performance-engineer
Job description: ### **The Mission** We are building a high-stakes mobile experience where "fast" is the baseline and "fluid" is the requirement. We need an engineer who is obsessed with the mechanics of mobile performance—someone who views a dropped frame as a bug and a 2-second loading state as a failure. You will be responsible for ensuring our app feels like a premium native product while handling complex, real-time financial data. --- ### **Core Responsibilities** #### **1. Performance & Stability** * **Zero-Lag Navigation:** Architect a 1-1 screen transition map (forward and backward) using Native Stack to ensure hardware-accelerated transitions. * **Frame Rate Optimization:** Maintain a locked 60 FPS (or 120 FPS on ProMotion displays) across all lists and complex views. * **Crash Management:** Implement and monitor rigorous error-tracking (Sentry/Crashlytics) to achieve a 99.9% crash-free rate, specifically debugging native-layer memory leaks and JS-thread hangs. #### **2. Real-Time Data & State Integrity** * **Instant Updates:** Engineer a sophisticated data-fetching strategy for "Mission Critical" info (Balance, Transactions, Recipients) that updates seamlessly when moving from background to foreground. * **Optimistic UI:** Implement "Instant-Success" patterns for payments and profile updates, ensuring the UI reflects user actions before the server round-trip is complete. * **Cache Strategy:** Design a robust local caching layer that eliminates loading spinners for returning users. #### **3. High-Fidelity Interaction** * **Declarative Animations:** Build physics-based, interruptible animations using `react-native-reanimated` that run exclusively on the UI thread. * **Gesture-Driven Design:** Implement "Native-feel" interactions (swipe-to-action, pinch-to-zoom) that respond instantly to touch. --- ### **Technical Requirements** * **The "Big Three":** Expert-level proficiency in `react-native-reanimated`, `react-native-gesture-handler`, and `react-native-screens`. * **Data Synchronization:** Professional experience with **TanStack Query (React Query)** or **SWR** for managing server state, polling, and background refetching. * **The Bridge & Beyond:** Deep understanding of the React Native architecture (Bridge vs. Fabric) and the ability to write custom **TurboModules** in Swift or Kotlin when JS performance hits a ceiling. * **List Mastery:** Proven experience optimizing large datasets using `FlashList` (Shopify) or highly optimized `FlatLists`. * **Profiling Tools:** Mastery of Flipper, React DevTools, and iOS/Android native profilers to identify and kill "Jank." --- ### **Key Performance Indicators (What success looks like)** * **TTI (Time to Interactive):** App launch to "ready" state in under 1.5 seconds on mid-range devices. * **Transition Latency:** Zero perceptible lag between screen taps and transition starts. * **Data Freshness:** Critical financial data must be verified/refetched within 200ms of app foregrounding. --- ### **Bonus Points** * Experience in the Fintech or Mobile Money space. * A portfolio that includes "Offline-First" applications. * Contributions to the React Native Open Source ecosystem.

View job listing ↗

The Saturday Briefing