Mobile IOS Developer

Salary: 1,000–1,200 PLN/day (B2B)

Work model: Poznań — 1 day in the office, 4 days remote

Why choose this offer?

• Impact on the development of the largest e-commerce system in Poland
• Flexible work organisation
• Long-term cooperation within a stable ecosystem
• Regular integration meetings

Project

The engineer assigned to the project should understand the intersection of native mobile development and the dynamic AdTech environment. In-app advertising is a complex ecosystem built on IAB (Interactive Advertising Bureau) standards.

A performance and UX mindset is required to balance monetisation objectives with user experience, ensuring that advertising scripts do not block the application’s main thread.

The role requires an iOS developer with JavaScript knowledge, comfortable using JavaScript in WebViews to investigate incorrectly reported ad-creative events while maintaining a strong foundation in the native technology stack.

The Senior Mobile Developer will support a team responsible for the technological aspects of advertising delivery and display within a mobile application.

Responsibilities

• Integrate and develop advertising components, including new video, display and native ad formats, directly in the main application.
• Optimise video ad playback, smooth transitions and the correct triggering of tracking events.
• Collaborate with Core Mobile teams to ensure alignment with application architecture and high standards of security and performance.
• Implement and maintain privacy solutions, including GDPR consent management (CMP), and adapt to system changes.
• Analyse and resolve issues between native application code, external advertising SDKs and web creatives.
• Participate in designing solutions requiring communication between the mobile application and advertising systems.

Expected competences and knowledge

• Over 5 years’ commercial experience developing native iOS applications with Swift.
• In-depth understanding of mobile architecture patterns, including MVVM, MVI and Clean Architecture.
• Practical WebKit and WKWebView experience, including native-to-web communication, handling JavaScript messages through WKScriptMessageHandler and invoking JavaScript code.
• Solid JavaScript and core web technology knowledge (HTML/CSS) for integrating and debugging web-based advertising content.
• Experience with RESTful APIs, asynchronous programming and efficient data processing.
• Proficiency in unit and integration testing.
• Knowledge of version control systems, such as Git.
• Solid understanding of software engineering principles, data structures and algorithms.
• Proactive problem-solving approach and passion for excellent user experiences.

Additional valued experience

• Large-scale, high-traffic mobile applications.
• Reactive programming, such as RxJava, RxKotlin or Combine.
• Jetpack Compose and coroutines.
• A/B testing frameworks.
• Open-source contributions or a strong GitHub profile.
• Agile/Scrum environments.

Technologies

• iOS
• Swift
• JavaScript
• WebKit
• REST API