Filament is hiring a Mobile Lead Engineer for a senior, product-facing role. You will be the primary mobile engineer on a well-defined, roadmap-driven client product, responsible for the quality, architecture, and delivery of native mobile applications on iOS and Android. You will be embedded in a multidisciplinary team, engage directly with clients, contribute to technical strategy, and help shape how mobile is delivered across the business.

What You'll Do

Take technical ownership and deliver a production native mobile application with an active product roadmap.
Make architecture decisions, ensure code quality, and ensure long-term maintainability across iOS and Android codebases.
Integrate proprietary and third-party SDKs, including binary frameworks with limited documentation.
Work on camera and real-time processing pipelines, runtime ML asset management, and multi-environment build configuration.
Manage local persistence with versioned schema migrations, analytics instrumentation, and error monitoring.
Integrate REST APIs for data management, content delivery, and data sync.
Handle localisation and runtime language management across multiple locales.
Contribute to broader mobile projects across client projects in IoT, health tech, sports tech, and other sectors.

What We're Looking For

Proven native mobile development experience on iOS, Android, or both in production, product-grade applications.
Experience taking technical ownership of a mobile product, from architecture and quality to roadmap input.
Comfort integrating proprietary SDKs and working with vendor-supplied binaries with limited documentation.
Experience with multi-variant or multi-flavour build configuration across environments.
Experience with SQLite-backed local persistence and schema migration strategies.
Experience with Firebase Analytics, Sentry, and REST API integration.
iOS: Swift 5.0+, Xcode 16+, UIKit (UIViewController, UICollectionView, UITableView, XIBs), CocoaPods, Swift Package Manager, MVC with protocol-based service abstractions, SQLite.swift and RealmSwift, XCConfig-based build configuration, embedding proprietary binary frameworks.
Android: Kotlin 1.9+ with Kotlin Coroutines; Android SDK API 34+, MVVM with LiveData, ViewModels, lifecycle-aware components, Room with DAOs and manual schema migrations; KAPT annotation processing, CameraX/Camera2 (core, lifecycle, view), integration of external SDKs via NDK/JNI, Gradle multi-flavour builds; ProGuard/R8 with build optimisations, Android Jetpack Compose, Hilt/Dagger, Jetpack DataStore, WorkManager.

Nice to Have

CI/CD tooling for mobile pipelines, such as Fastlane or equivalent.
Experience working in regulated industries like medical devices or financial services.

Technical Stack

Swift, Xcode, UIKit, CocoaPods, Swift Package Manager, SQLite.swift, RealmSwift, Kotlin, Kotlin Coroutines, Android SDK, MVVM, LiveData, ViewModels, Room, KAPT, CameraX, Camera2, NDK/JNI, Gradle, ProGuard/R8, Jetpack Compose, Hilt/Dagger, Jetpack DataStore, WorkManager, Firebase Analytics, Sentry, REST APIs, Core ML (optional), ML Kit (optional), Fastlane.

Team & Environment

You will be embedded in a multidisciplinary team that includes fullstack engineers, product designers, cloud engineers, electronics engineers, and data scientists.

Benefits & Compensation

Flexible working times/hours.
Company pension scheme.
Hybrid work available (office in Glasgow min 2 days/week).
Provision of development hardware (MacBook + 2 x screens + test hardware).
Supporting online learning/training courses.
A lead role with real product responsibility.
Exposure to a wide variety of client problems across industries.
A multidisciplinary team with unusually broad capability.
The chance to shape how mobile is delivered across a growing, ambitious professional technology consultancy.