iOS Senior Engineer

At FDJ UNITED, we don't just follow the game, we reinvent it.

FDJ UNITED is one of Europe’s leading betting and gaming operators, with a vast portfolio of iconic brands and a reputation for technological excellence. With more than 5,000 employees and a presence in around fifteen regulated markets, the Group offers a diversified, responsible range of games, both under exclusive rights and open to competition. We set new standards, proving that entertainment and safety can go hand in hand. Here, you’ll work alongside a team of passionate individuals dedicated to delivering the best and safest entertaining experiences for our customers every day.

We’re looking for bold people who are eager to succeed and ready to level-up the game. If you thrive on innovation, embrace challenges, and want to make a real impact at all levels, FDJ UNITED is your playing field.

Join us in shaping the future of gaming. Are you ready to LEVEL-UP THE GAME?

What you’ll work on

• Build and evolve SwiftUI feature modules across the KSP stack
• Integrate KSP into the Sports host app via shared contracts
• Design and maintain modular SPM APIs, keeping module boundaries clean and public surfaces intentional
• Implement real-time sportsbook experiences: odds/live data flows, navigation, analytics, localization, and media
• Own quality end-to-end: unit tests, SwiftUI view tests, lint/format, CI feedback, and PR hygiene
• Collaborate with product, design, QA, and other platform teams on high-impact sportsbook journeys

Our tech stack (what you’ll use day to day)

• Language & platform: Swift 5.10+, SwiftUI, iOS 17+, Xcode
• Architecture: Modular Swift Packages, feature-oriented modules composed through an integration layer
• Dependency injection: Factory (Container-based DI, test/preview-friendly registrations)
• Concurrency & reactivity: Structured concurrency (async/await), preference for modern Observation patterns 
• Networking & realtime: REST-style providers plus MQTT/WebSocket for live offering data
• Testing: Swift Testing (preferred for new tests), ViewInspector for SwiftUI
• Tooling & delivery: SwiftLint, SwiftFormat, Git hooks, Jira, GitLab, Jenkins/CI, Fastlane

Ideal profile

Must-have

• Solid commercial experience building production iOS apps or libraries in Swift
• Strong SwiftUI skills: composition, navigation, state management, performance-aware UI
• Comfortable with modular Swift Package development and multi-repo / multi-package dependency graphs
• Practical experience with async/await and main-actor boundaries, able to reason about concurrency bugs
• Experience writing unit tests and testing UI behavior (XCTest and/or Swift Testing)
• Ability to work in a large codebase with shared components, strict linting, and CI gates
• Clear communication in English and confidence collaborating across squads

Nice-to-have

• Experience with Factory, Resolver, or similar DI containers
• Exposure to Combine and migration toward Observation / @Observable
• Realtime systems experience (MQTT, WebSockets, push-driven UI)
• Sportsbook, betting, trading, or other high-frequency / odds-driven product experience
• Experience embedding libraries into a host app (SDK-style delivery, integration contracts, versioning)
• Familiarity with analytics/tracking instrumentation, localization pipelines, or media/player SDKs
• Comfort with GitLab, conventional PR reviews, and Jira-linked delivery

What success looks like

• You deliver reliable sportsbook features with clean module boundaries and predictable integrations
• You write testable, maintainable Swift that fits existing KSP conventions 
• You improve live UX quality under real conditions: odds updates, navigation, betslip flows, and streaming
• You leave the codebase healthier than you found it: better tests, clearer APIs, fewer regressions

Soft skills we value

• Product mindset: you care about customer journeys, not only tickets
• Pragmatism: prefer simple solutions, abstract complexity only when needed
• Ownership: you follow work through build, test, review, and production feedback
• Collaboration: you can partner with web / backend sportsbook teams and host-app iOS engineers

We believe talent knows no boundaries. Our hiring process focuses solely on your skills, experience, and potential to contribute to our team. We welcome applicants from all backgrounds and evaluate each candidate based on merit, regardless of personal characteristics as the age, gender, origin, religion, sexual orientation, neurodiversity or disability.