Senior iOS Engineer

Right now is one of the most exciting moments to join Popsa. Deloitte named us one of the UK’s fastest-growing technology companies, and the Financial Times recognised Popsa among the Top 5 fastest-growing software companies in Europe. We’re backed by world-class investors, and the world is noticing. Our iOS and Android apps are available in 12 languages, trusted by more than 12 million people who have created over 5 million photobooks shipped to 50+ countries. With more than 350,000 five-star reviews, we’re one of the highest-rated consumer apps anywhere. But the real story isn’t the numbers, it’s the memories behind them. We’re living in a time where we capture more photos than ever before. Billions of moments sitting unseen in camera rolls and clouds, mixed with screenshots, receipts, or where we parked the car. We are great at documenting life… but not so great at preserving the meaning in it. Popsa is changing that. Since launching in 2016, we’ve built an award-winning platform that removes every barrier to transforming your favourite memories into something beautifully tangible. No design skills. No time-sink. Just the joy of holding real stories in your hands. A celebration of the people and moments that make life worth living. This is only the beginning. 👉 Learn more about what it’s like to work at Popsa 👉 Read about the technology we're building 👉 Take a look inside our Soho HQ About the Role You'll be building and improving a sophisticated memory curation platform that helps users discover their best moments, and create beautiful, personalised products automatically. The app intelligently curates photos from users' libraries, uses on-device ML for face recognition and photo analysis, and renders high-fidelity 3D previews of physical products. You'll work across features spanning photo selection, AI-assisted layout generation, payment processing, and immersive product visualisation. To learn more about this role or the company, contact us through https://popsa.com/careers. If you’re the sort of person who cares about the detail, and stays kind under pressure, you’ll fit in. country: GB all locations: [Soho, London] commitment: Full-Time department: Product Engineering location: Soho, London team: Native Mobile Engineering Expertise: We’re primarily looking for recent experience developing high-quality, consumer-facing iOS apps where finesse, performance, and delight are priorities. Strong experience developing production apps with SwiftDeep understanding of UIKit architecture, with growing proficiency in SwiftUI for building modern UI components in a hybrid codebaseFamiliarity with the Coordinator pattern for managing complex navigation flowsExperience with MVVM and protocol-oriented designUnderstanding of the iOS app lifecycle, including background tasks, widgets, and app extensionsProficiency handling resources, permissions, and responsive UI across device sizes Mindset: A problem-solving, curious, and inquisitive attitudeClear communicator with a keenness to work collaborativelyConstructive approach to code reviews and architectural discussions Nice to Have: Experience with custom drawing, Core Graphics, or advanced UI animationsPerformance optimisation and profiling with InstrumentsAccessibility best practices and VoiceOver supportExperience integrating on-device ML models (CoreML, Vision)Background in 3D graphics or AR experiencesFamiliarity with localisation workflows for international apps Tech Stack: Architecture & dataSwift Package Manager for modular dependency managementProtocol Buffers for efficient data serialisation with our backendCore Data for on-device persistenceRepository pattern for clean data access abstractionsConcurrency & reactive programmingSwift Structured Concurrency (async/await, actors)Combine for reactive data flows and UI bindingsGraphics & visualisationSceneKit and ARKit for immersive 3D product previewsCustom Metal shaders for advanced rendering effectsVision and CoreML for on-device photo analysis and face recognitionPhoto library integrationDeep PhotoKit integration for accessing and analysing user photo librariesOn-device ML models for face embeddings and photo quality scoringSmart album generation and photo metadata synchronisationThird-party integrationsFirebase (Analytics, Remote Config)Sentry for crash reporting and performance monitoringStripe and Braintree for payment processingGrowthBook for feature flags and experimentationNuke for high-performance image loading and cachingCI/CD & qualityGitHub Actions for automated linting, testing, and snapshot testingXcode Cloud for continuous integrationFastlane for release automationSwiftLint for code style consistencySnapshot testing for UI regression prevention