Lead React Native Engineer - Canada

Role summary. Lead engineer on the delivery team. Owns the highest-complexity screens and integrations. Responsibilities. Deliver highest-complexity screens and integrations across three delivery waves. Set engineering patterns, reference implementations, and code standards for the team. Pair with the client's engineers on paired-programming and knowledge transfer. Own payment integration, Auth0 identity flow, and push notification architecture at code level. Lead pull request reviews. Contribute to Architecture Decision Records. Support the four self-sufficiency exercises during hypercare (deploy hotfix, onboard from KB, restore during simulated P1, extend using established patterns). Must-have technical experience 8+ years mobile engineering, minimum 5 years hands-on React Native in production. Direct production experience with React Native 0.76+ and the New Architecture (Bridgeless, TurboModules, Fabric). Strong TypeScript, comfortable with strict mode. Hands-on with Hermes engine and Expo SDK 52 prebuild. Direct experience with TanStack Query and Zustand. Detox authorship for end-to-end mobile tests, both iOS and Android. Prior integration of Apple Pay and Google Pay (tokenised payment handles). Prior integration of Auth0 or equivalent OIDC identity in mobile. Prior implementation of APNs and FCM push notifications, including token migration on version upgrades. Universal Links and App Links deep-link routing. Native platform expertise (required). Comfortable reading and writing native iOS (Swift or Objective-C) and native Android (Kotlin or Java) at the level required to author or maintain TurboModules bridging native SDKs into React Native. Prior experience with iOS Keychain and Android Keystore for secure token storage. Migration and replatform experience (required). Direct experience on at least one mobile replatform from native to React Native, in production. Understanding of auth token migration, push token re-registration, cached data reconciliation on first launch after replatform. Industry background (preferred). Regulated Canadian mobile experience (public sector, transportation, financial services). Bilingual (English and French) app delivery experience. WCAG 2.1 or 2.2 accessibility delivery.