I'm Dzionis — a senior iOS engineer in Warsaw. Over 10+ years I've designed and shipped 50+ App Store apps, from simple REST clients to geolocation and AR. I've led iOS teams, mentored juniors, and these days I also build and ship my own products.
End-to-end iOS — from the first Xcode project to the App Store listing. Here's what I'm working on now, plus highlights from a decade of releases.
Interval running for Apple Watch. Build a workout, run it from your wrist, and review the route afterward. Watch-first, with no subscription wall.
Fast conversion across 160+ world currencies with daily-updated rates — a small, focused travel companion that doubled as a real growth experiment.
Turns any text, document or photo into natural-sounding speech — listen instead of read, whether you're studying, working or on the move.
Full-stack when needed: I built PartyCam's backend in Python on Firebase (Firestore + Cloud Functions), plus PHP chat backends on other projects.
From web and backend beginnings to leading an iOS team and going independent — releasing apps the whole way.
Building and shipping my own products — iRunning chief among them — and running the growth side myself, from App Store optimization to release strategy.
Developed and supported five App Store apps (izi AI, izi Type, PartyCam, Edith) across internal and outsourced projects, with ongoing updates and refactoring — and built backend services too: PHP for chat, Python on Firebase for PartyCam.
Led the iOS team — architecture, project management, mentoring junior developers, and working directly with foreign clients. Shipped 5+ App Store apps (Drive&Pay, Tix, Дзякуй, Звезда and others) and helped run the company's internal education program of weekly talks and workshops.
Built and released three App Store apps on long-term client projects, with regular updates and refactoring.
Shipped 10+ App Store apps, owned architecture on iOS projects, mentored juniors, and contributed to internal education — workshops and news digests.
Prototyped and shipped 5+ iOS apps for the agency and its clients.
Where it started: Yii-based CMS, Yandex widgets, social-promotion tools, and backends for mobile apps.
A decade of iOS, from language internals to monetization and CI/CD — the stack I reach for, end to end.
Short, practical write-ups on the things I hit while shipping. First full posts are going up now — more on the way.
I'm a senior iOS engineer based near Warsaw, with 10+ years building for the platform and 15+ years in software overall. I've shipped 50+ apps to the App Store — from straightforward REST clients to geolocation and AR — for startups and mid-size companies.
Along the way I led an iOS team, owned architecture, mentored junior developers, and worked directly with international clients. When a product needed it, I went full-stack — building backends in PHP and Python on Firebase.
These days I build and ship my own products, like iRunning, and stay close to the parts beyond the code — App Store optimization, growth, and the craft of a release people actually keep. I work across English, Polish and Russian.
Senior iOS engineer, open to strong product work, contracts and collaborations. Quickest ways to reach me: