Mostafa Salah Eldeen

Senior iOS Engineer (Contract)

• Job Details:Led end-to-end development of scalable weather modules using SwiftUI and SDUI, enhancing UI responsiveness and maintainability. Architected and integrated advanced analytics systems across the app lifecycle, improving data-driven decision-making and performance insights. Replaced the JWPlayer framework with a custom native video solution, improving playback performance by 15% and reducing memory usage. Optimized Google Ads integration, increasing ad load efficiency and revenue performance by 20%. Strengthened app stability by introducing automated UI testing pipelines, contributing to a measurable reduction in crash rate. Spearheaded iOS hiring for the ads team, selecting top talent and streamlining the evaluation process. Collaborated with cross-functional teams across global time zones, ensuring seamless delivery and continuous alignment.

Senior iOS Engineer (Contract)

• Job Details:Refactored app architecture into a modular MVVM-C structure, enhancing maintainability and onboarding speed for new developers. Reduced crash rate by 15% through advanced threading and concurrency optimization across high-traffic modules. Collaborated closely with product and QA teams to launch a performance-critical release under tight SLAs.

Senior iOS Engineer

• Job Details:Led the successful migration of a legacy Objective-C codebase to Swift, improving maintainability, performance, and long-term scalability. Engineered and deployed secure VoIP call and appointment booking features, meeting healthcare compliance and reliability standards. Defined and executed a UI and snapshot testing strategy, reducing regressions and bug rates by 18%. Bridged coordination gaps between backend and frontend teams, accelerating feature delivery and reducing blockers. Played a key role in recruitment and mentoring, enhancing team capability and accelerating onboarding efficiency.