Community Leaders

We are Open Source community leaders

We are well-known in the React Native community, contributing to many Open Source projects, and organizing the first European React Native conference - React Native EU.

React Native conference 1
Developers

Meet the team of React experts

We are a team of Open Source freaks that are willing to go an extra mile with every project we dive into. Check us out!

Mike Grabowski

Mike Grabowski

@grabbou

Co-Founder & CTO

Co-Founder & CTO of Callstack. Mike is a React Native core contributor and the author of libraries like RNPM and Haul. Mike makes sure our infrastructure performs well to its limits.

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Satyajit Sahoo

Satyajit Sahoo

@satya164

Software Developer

Satya is in Facebook’s 2016 TOP 5 external contributors list. You can find him everywhere. Satya is also a React & React Native ninja that will make your apps stand above the crowd.

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Mike Chudziak

Mike Chudziak

@mikechudziak

Lead Software Engineer

Software developer working all across the stack, always glad to help you manage the technical aspect of a project and lead your team to success. Experienced in the native mobile and web development. Big lover of GraphQL.

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Ferran Negre Pizarro

Ferran Negre Pizarro

@ferrannp

Software Developer

Software developer with broad experience in delivering first class React & React Native applications. Ferran develops Android apps as a hobby. He will also make sure you use Jest and test your code!

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Michał Pierzchała

Michał Pierzchała

@thymikee

Software Developer

JavaScript developer passionate about building mobile and web. Michal enjoys improving tooling and code quality, learning, and giving back to OSS community. Core Jest contributor.

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Jakub Kłobus

Jakub Kłobus

@souhe

Software Developer

Software developer working at Callstack since the beginning. After mastering web, he moved to React Native where he focuses on making React Native Windows next big thing.

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Wojtek Szafraniec

Wojtek Szafraniec

@wojteg1337

Software Developer

Software developer working with React and React Native. He likes to cooperate with the team. Big fan of MobX and clean code. Always ready to learn new things.

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Piotr Drapich

Piotr Drapich

@dratwas

Software Developer

JavaScript developer working full-time with React (Native). Having worked on the backend for quite some time, he mastered building apps with REST to its limits.

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Łukasz Walczak

Łukasz Walczak

@lukewalczak

Software Developer

JavaScript developer who likes finding the most all-purpose solutions. He is characterised by a precise and methodical approach to the problem. Open to new technologies and development opportunities.

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Paweł Trysła

Paweł Trysła

@zamotany

Software Developer

Fullstack Developer, the tooling guy with extensive knowledge of Webpack and Babel. Huge fan of Electron, functional programming and RxJS.

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Krzysztof Borowy

Krzysztof Borowy

@krizzu

Software Developer

Software developer with a passion for mobile development. Highly interested in native mobile and cross-platform world. You can find him tinkering with React (Native) and Android/Kotlin stuff.

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Adam Trzciński

Adam Trzciński

@adamtrz

Software Developer

JS dev focused on enhancing his skill set every day. Passionate with learning and getting to know new techs and skills.

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Krzysztof Sroka

Krzysztof Sroka

@kpsroka

Software Developer

Versatile software developer experienced in building highly scalable web apps. Focused on creating well-written and thoroughly tested code.

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Łukasz Czyszczonik

Łukasz Czyszczonik

Software Developer

JavaScript developer, wants to know new stuff and learn new technologies every day. Fan of React (Native), CI, Node.Js, and mainly GraphQL. Fullstack everyday.

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Dawid Urbaniak

Dawid Urbaniak

@trancever

Software Developer

JavaScript developer passionate about web and mobile development. Mostly working with React, React Native and Node.js. Fan of Redux and functional programming.

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Magdalena Markusik

Magdalena Markusik

@mmarkusik

Software Developer

Software developer passionate about both frontend and backend technologies, including JavaScript, Ruby, and Python. Fan of functional programming and clean code. In her free time, she likes to create artwork and take care of her pet - snake.

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Kacper Wiszczuk

Kacper Wiszczuk

@esemesek

Software Developer

Software Developer who enjoys working on the full stack. Huge fan of TypeScript, Test Driven Development and obviously React. Kacper spends his free time constantly improving his engineering skills and learning new technologies.

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Jakub Mazurek

Jakub Mazurek

@jaysbytes

Software Developer

TypeScript enthusiast experienced with React and Node. He feels best in creating solutions from scratch, making proof of concept projects and experimenting with new technologies. In his free time, he enjoys various outdoor activities like hiking and riding a bike.

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Callstack

Meet the silent heros behind our success

Our company delivers a ton of great software thanks to our marketing, business and HR teams.

Anna Lankauf

Anna Lankauf

Co-Founder & CEO

Co-Founder & CEO of Callstack. Anna is a young entrepreneur, having graduated from psychology, that has also a broad expertise as a UX Strategist. Anna makes sure that Callstack grows one step at a time.

Agnieszka Czmochowska

Agnieszka Czmochowska

Finance and Administration Manager

Finance and Administration Manager. Can’t quit sports and, most of all, basketball, without which she couldn’t bare to live. In her spare time, she likes to travel and try different cuisines.

Krzysztof Pawlak

Krzysztof Pawlak

Project Manager

Natural born project manager who loves to be involved deeply in projects. He ensures project quality and the regularity of progress and pays attention to both technical and business aspects.

Monika Garyantesiewicz

Monika Garyantesiewicz

Marketing Strategist

Marketing Strategist at Callstack. Monika is a Passionate Marketer, having graduated from the economy, that has also a Professional Diploma in Marketing powered by Chartered Institute of Marketing in London. Monika makes sure that Callstack brand image and a development is going in the right direction.

Mateusz Sławiński

Mateusz Sławiński

Talent Manager

Talent Manager watching over the well-being of our team. Experienced recruiter always looking for new talents to join Callstack. Passionate about cinema and football. Dog person.

Let's work together

Need help with React or React Native? Let us know!