Kirlos Yousef

Computer Science, BSc

2017 - 2020

University of Debrecen (Debrecen, Hungary)

• Graduated with the highest GPA in the class on a fully funded scholarship

RaceMe!

Competitive social running app (iOS/watchOS)
Available on the App Store

• Engineered a hybrid real-time multiplayer engine combining Firestore for document sync and BrainCloud RTT for event-driven matchmaking, achieving low-latency state synchronization for concurrent racers
• Developed a fault-tolerant background location service using CoreLocation, handling aggressive OS suspension policies to ensure reliable race tracking while the device is locked
• Built a bidirectional WatchConnectivity layer to sync high-frequency race telemetry between iOS and watchOS, optimizing payload size to prevent WCSession throttling
• Shipped Live Activities & Dynamic Island integrations, allowing users to track real-time race progress on the lock screen without app foregrounding

Revera AI

Intelligent voice recorder & AI transcriber
Available on the App Store

• Architected a fault-tolerant transcription engine (SFSpeech/Whisper) with seamless offline failover
• Reduced data upload usage by ~80% via an AVFoundation pipeline downsampling 44.1kHz stereo to 16kHz mono on the fly
• Ensured data integrity with a SwiftData persistence layer handling audio interruption recovery and disk space monitoring

Amour

A Space fo Couples
Available on the App Store

• Engineered a thread-safe, dual-layer image caching system (Memory + Disk) with strict cost limits (50MB), eliminating Out-Of-Memory crashes during infinite scroll sessions
• Optimized data fetching by implementing custom PostgreSQL RPCs (Remote Procedure Calls) to handle heavy filtering (blocking/pagination) on the server, reducing client-side payload size by ~40%.
• Built a universal routing system handling Deep Links and Push Notifications, ensuring consistent navigation state across cold launches and background operational modes

Senior iOS Engineer & Tech Lead

2025 – Present

Sellou — Utah, United States (Remote)

• Spearheaded iOS technical strategy and roadmap planning with the CEO, translating product goals into scalable architecture
• Architected V2 video engine (AVKit/HLS), reducing playback start time by 40% via intelligent pre-buffering and HLS optimization
• Reduced app bundle size by 20% using On-Demand Resources and Asset Slicing for non-critical resources
• Built secure Stripe Connect module handling payouts and ensuring PCI compliance, achieving 99.9% crash-free session rate
• Engineered the “Plot My Calories” AI vertical with OpenAI Vision and Swift Actors to keep UI at 60fps during heavy processing
• Established automated CI/CD pipelines for both production apps, cutting release cycle overhead by 50%

iOS Team Lead

2024 – 2025

Iomob – The Internet of Mobility — Barcelona, Spain (Remote)

• Led a team of 5 iOS engineers to deliver 2 enterprise apps with crash-free rate >99.9%
• Accelerated delivery and reduced technical debt by implementing automated CI and standardized code reviews
• Delivered LNER (UK Rail): Stripe tokenization for PCI-compliant payments, cutting checkout time to <8 seconds, and reduced trip-planning wait times by 35% via caching and pre-fetching
• Launched BrightBike (Palm Beach): real-time bike-sharing with offline-first map clustering and local receipt generation for low connectivity

iOS Engineer

2021 – 2024

Iomob – The Internet of Mobility — Barcelona, Spain (Remote)

• Engineered the core iOS Mobility SDK used by Ford and Renfe, normalizing data from 10+ providers (Uber, Bolt) to cut integration time to <2 days
• Optimized a heavy data synchronization engine handling 10+ provider streams via custom concurrent queues, maintaining 60fps scroll performance
• Achieved 90%+ code coverage on core SDK logic and zero critical crashes by implementing comprehensive Unit & UI testing