Sieński Witold
Engineering Teams Manager at XTB
Warsaw, Masovian Voivodeship, Poland
Summary
👤
Senior🎓
Top SchoolSieński Witold is an engineering leader with 10 years of experience building and managing mobile teams, currently serving as Engineering Teams Manager at XTB in Warsaw. He combines hands-on Android expertise and project management—having led development of xStation (≈0.5M installs) and high‑scale selfcare apps—with a strong advocacy for Clean Architecture, SOLID principles and automated testing. As a former tech lead, team leader and co-founder, he excels at bridging business and IT, recruiting and upskilling teams, and shaping product-facing UX and architecture. He has shipped production Android apps across finance, telecom and enterprise domains, often coordinating cross-functional squads including backend, design and QA. Known for logical problem solving and a steady stream of practical, innovative ideas, he adapts quickly to new teams and challenges. Never saying "never," he continues to learn and pursue opportunities that improve app quality and team performance.
10 years of coding experience
11 years of employment as a software developer
Warsaw University of Technology
English, German, Polish
Github Skills (13)
dialog7
android-library6
dialogs6
java5
android5
kotlin4
dialogfragment4
color-picker3
material-design3
sdk-android3
sdk2
verification2
identity1
Programming languages (2)
Github contributions (5)
peoxnen/AndroidTestIntegration
Jul 2016 - Jul 2016
Contributions:28 commits, 27 pushes, 1 branch in 18 days
peoxnen/DesignPatterns
Jul 2016 - Aug 2017
Contributions:16 pushes, 1 branch in 1 year 1 month
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