Senior Mobile Engineer (React Native + native iOS/Swift): real-time video and AI interview app

About us MyDirector turns recorded conversations with an AI interviewer into short-form video clips for founders and executives. We have paying customers and a production web app (Next.js and TypeScript, LiveKit for real-time video, Python AI agents). We're building our first mobile app: iOS first, Android to follow. You'll work directly with our two founding engineers. We're full-stack, not mobile, so we need you to own the mobile side technically. What you'll build - A React Native (Expo, custom dev builds) app for iOS, and later Android - A native Swift module that runs one camera/mic capture session feeding both a live LiveKit WebRTC call and a local high-quality recording (AVFoundation / AVAssetWriter) at the same time - Reliable, resumable background upload of large video files (hundreds of MB) to signed URLs, with server-confirmed completion - Robust handling of interruptions (calls, backgrounding, screen lock), thermal pressure and permissions - Sign-in (Firebase Auth / Identity Platform + Sign in with Apple) and integration with our REST API - TestFlight and App Store releases Must have - 4+ years of mobile development, with at least one shipped App Store app you can show - Real native iOS experience in Swift: you've written React Native native modules, not just installed libraries - AVFoundation (capture sessions, AVAssetWriter, audio sessions) - WebRTC experience (LiveKit, Twilio, Agora, Daily or similar) - Background transfers on iOS (URLSession background tasks) - Comfortable being the mobile technical lead and making and explaining architecture decisions - At least 4 hours of overlap with Central European Time (CET), and clear written English - Your own Mac and a physical iPhone. Camera capture can't be tested in the iOS Simulator. Nice to have - LiveKit's Swift or React Native SDK specifically - Android / Kotlin - Experience with apps that record video, audio or live streams How we work - Starts with a paid 2-week technical spike: a proof of concept on a real device. If it goes well, it becomes a long-term full-time contract (40 h/week). - Weekly demo on a real device, PR-based code review, CI from day one - All code, Apple accounts and signing certificates live in our organization To apply, answer briefly (generic proposals will be skipped) 1. Start your proposal with the word "AVCapture". 2. Link an App Store app you built and say which parts you wrote yourself. 3. Have you written a Swift native module for React Native? What did it do? 4. On iOS, how would you send one camera feed to a WebRTC call and record it to a local file at the same time? Two or three sentences. 5. How would you make sure a 500 MB upload finishes if the user locks their phone?