Senior iOS Developer (Mobile Commerce)

About the roleWe are looking for a Senior iOS Developer to build and improve a high-traffic retail shopping app. The app runs on the POQ app-commerce platform, with SAP Commerce Cloud as the e-commerce backend.You will own key parts of the shopping journey, from product browsing and product detail pages to basket and checkout. The focus is a fast, stable app that handles large product catalogues, many images and peak trading traffic without slowing down or crashing.What you'll doBuild and maintain features in Swift across the shopping journey: product listing, product detail pages (PDP), search, basket, checkout and order history.Apply MVVM and clean architecture so screens stay testable, reusable and easy to change.Build checkout flows that handle complex orders, including splitting one order into several shipments based on store and warehouse stock.Design and maintain a clean networking layer for REST APIs, with typed models, error handling, retries and authentication.Use caching (NSCache, URLCache, on-disk storage) to keep PDP and catalogue screens fast.Optimise image loading and memory use for image-heavy product screens.Support offline use, persist product and cart data, and keep the cart in sync across devices and sessions.Find and fix crashes, memory leaks and slow screens using Instruments, Xcode Memory Graph and Firebase Crashlytics.Keep the UI smooth using Swift concurrency (async/await, actors), GCD and OperationQueue where each fits best.Own release delivery: certificates, provisioning profiles, TestFlight builds, App Store submission and CI/CD pipelines.Work with backend, design, QA and product teams on POQ configuration and SAP Commerce APIs.What you'll bringSwift and iOS SDK: strong Swift, UIKit and SwiftUI, with a solid grasp of memory management (ARC, retain cycles, weak/unowned).Architecture: MVVM and MVC, and when to use each; clean architecture, coordinators, dependency injection and protocol-oriented design.Networking: URLSession, Codable, a modular API layer with request builders, error mapping, token refresh and retry logic.Concurrency: async/await, Task, actors and MainActor; GCD and OperationQueue for older code and dependent tasks.Caching and persistence: NSCache, URLCache and disk caching; Core Data, SwiftData or Realm; offline-first data and cart sync.Image performance: downsampling, prefetching, cell reuse and libraries such as Kingfisher or SDWebImage.Debugging and monitoring: Instruments (Time Profiler, Allocations, Leaks), Xcode Memory Graph and Firebase Crashlytics, including dSYM symbolication.Release management: certificates, App IDs, provisioning profiles, signing, TestFlight and App Store Connect review.E-commerce experience: at least one shipped retail or e-commerce app covering PDP, basket and checkout.Engineering practice: Git, unit and UI testing (XCTest), code review, and CI/CD with Xcode Cloud, Fastlane, Bitrise or GitHub Actions.Nice to haveExperience with the POQ app-commerce platform or a similar mobile commerce SDK (Shopify Mobile Buy SDK, Salesforce Commerce Cloud, commercetools).Working with SAP Commerce (OCC) APIs from a mobile app.Apple Pay, payment SDKs (Adyen, Stripe, Klarna) and secure storage with Keychain.Push notifications, deep links and universal links, and analytics tools (Firebase Analytics, Adobe, Amplitude).Combine, Swift Package Manager and modular app design.Accessibility (VoiceOver, Dynamic Type) and localisation for multiple markets.Some Android or Kotlin exposure.Experience and qualifications5–9 years in mobile development, including 4+ years building native iOS apps in Swift.At least 2 apps released to the App Store, ideally including a retail or e-commerce app with high daily traffic.Proven record of improving app stability (crash-free rate) and performance in production.Bachelor's degree in Computer Science or equivalent practical experience.Clear written and spoken English, and comfortable working with designers, backend engineers and product owners.Calm ownership of production issues and release deadlines, especially during peak trading.