About
Oskar Kwaśniewski is co-founder and CTO of TesterArmy, a Y Combinator company. He has contributed extensively to React Native with over 100 merged pull requests and created multiple open-source libraries. He has worked with companies including Vercel, Meta, and AT&T.
Founder at TesterArmyYC X26
Intro paths
YC
Oskar went through Y Combinator (Spring 2026) — any YC alum in your network can reach them through the YC community.
GP
Their group partner at YC was Pete Koomen, General Partner at Y Combinator — the partner who ran TesterArmy's batch and knows the company first-hand. YC profile ↗
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In turn, Oskar can intro founders to TesterArmy's investors below.
TesterArmy's investors · 1
Co-founders at TesterArmy
SR
Szymon RybczakFounder
Experience
- TesterArmy (YC P26)Co-Founder & CTOcurrent2026 — presentRejon Zatoki San Francisco
- CallstackSenior React Native Developer2022 — 2026
- MyMusicReact Native Developer2021 — 2022
- eTechnologie.pl - wykorzystaj potencjał Internetu!Frontend Web Developer2019 — 2021Szczecin, Woj. Zachodniopomorskie, Polska
Skills & more
iOS Development1Android Development1TypeScript1Typescript1Angielski1KomunikacjaSwift2Objective-C2Kotlin1Java1iOSAndroid
+10 more
React NativeJavaScriptRESTPHPWordPressCSSSQLReactJSHTML5GitFrom Oskar's professional profile.
Frequently asked questions
- Who is Oskar Kwaśniewski?
- Oskar Kwaśniewski is co-founder and CTO of TesterArmy, a Y Combinator company. He has contributed extensively to React Native with over 100 merged pull requests and created multiple open-source libraries. He has worked with companies including Vercel, Meta, and AT&T.
- Where does Oskar Kwaśniewski work?
- Oskar Kwaśniewski is Founder of TesterArmy.
- What companies did Oskar Kwaśniewski found?
- Oskar Kwaśniewski founded TesterArmy.
- Where did Oskar Kwaśniewski go to school?
- Oskar Kwaśniewski studied at West Pomeranian University of Technology in Szczecin (Bachelor's degree, Computer Science).
Founder mafias
Y Combinator mafia8,773
Also came through, then founded or led a company.
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+ 8,766 more
