+25%
Faster feature releases after implementing a feature toggle system in a fintech product.
Senior iOS Engineer / Based in Poland
Building polished iOS products that scale to millions.
I help product teams ship high-quality mobile experiences with a focus on SwiftUI, TCA, accessibility, performance, and complex UI systems that hold up in real-world production.
6+
years in production iOS engineering
10M+
MAU product experience
EU
open to senior roles across Europe
Strongest fit: SwiftUI, TCA, Accessibility, Design Systems, Performance, Architecture Modernization
Selected Impact
Outcomes that matter in real products.
12.5% → 31.2%
Test coverage growth that reduced average bug-fix time by 22.3%.
~35%
Faster screen development enabled by a reusable design system in a large-scale fitness app.
2m 14s → 3m 9s
Session duration improvement after resolving critical graph rendering issues.
Experience
Built across consumer, fintech, fitness, and commerce.
Global coffee retail app with 10M+ MAU
Working on a large-scale consumer product where UI quality, accessibility, localization, and platform evolution all matter at the same time.
- Adapted the app UI to Liquid Glass while resolving framework limitations around safe areas, scroll behavior, and rendering.
- Improved accessibility across critical journeys and supported a large localization migration to String Catalog.
- Contributed to Objective-C to Swift migration work inside a mature codebase.
SwiftUI · TCA · UIKit · VIPER · XCTest · async/await
Fintech product focused on South Africa
Drove measurable product improvements through release tooling, testing, onboarding surfaces, and performance fixes.
- Implemented a feature toggle system that accelerated feature releases by 25%.
- Increased test coverage from 12.5% to 31.2%, reducing average bug-fix time by 22.3%.
- Fixed graph rendering issues that improved session duration and introduced in-app banners that increased feature adoption by 15%.
UIKit · SwiftUI · Combine · XCTest · MVVM · Alamofire · SnapKit · AppsFlyer · SciChart
Large-scale fitness tracking application
Helped improve developer velocity and product engagement in a high-load fitness platform used across multiple regions.
- Built reusable design system components that reduced screen development time by roughly 35%.
- Delivered profile enhancements around stats and achievements to improve engagement and session duration.
- Refactored the networking layer with Moya to improve maintainability and testability.
UIKit · RxSwift · RxCocoa · MVVM · Moya · URLSession
German e-commerce platform
Focused on performance, conversion, and image-heavy catalog flows where responsiveness directly influenced the shopping experience.
- Developed a one-tap reordering flow that improved conversion for repeat users.
- Reduced memory usage on catalog screens from over 300 MB to under 250 MB.
- Built an abstraction layer for image handling that improved loading speed and scroll performance.
UIKit · RxSwift · RxCocoa · MVVM · SnapKit · Alamofire
What I Bring
Senior-level iOS judgment with a product mindset.
Complex UI Systems
Comfortable with custom interaction patterns, polished motion, and edge cases where standard components stop being enough.
Framework-Level Problem Solving
I enjoy diagnosing platform limitations and building practical solutions that keep the product moving instead of blocking on the framework.
Accessibility And Localization
Experience improving VoiceOver and focus behavior, and supporting products that need to work cleanly across many locales and user flows.
Architecture Evolution
Strong across modern SwiftUI code as well as UIKit and legacy systems, with hands-on experience in migration work and long-lived codebases.
Core toolkit
Swift · Objective-C · SwiftUI · UIKit · TCA · Combine · RxSwift · XCTest · Moya · Alamofire · Realm · CoreData · Metal · Fastlane · SPM · CocoaPods
Outside Work
Still building when the day job ends.
Engineering contest
Crypto wallet built from scratch for a TON competition
Designed and shipped the full product independently and received a $3,000 award.
Telegram contest
Drawing app with Apple Pencil support
Built a custom creative tool for iPad and received an $800 award.
Contact
Open to the next product challenge.
If you are hiring a senior iOS engineer who can improve product quality, tackle tricky UI problems, and ship reliably inside large-scale teams, I would love to talk.