<React + Native Special Forces />

Hire open source consultants for your next project. Specializing in React, React Native, and Node.js

Behind Callstack

Mike Grabowski

We are Callstack, a Europe-based dev shop with a strong focus on the open source and the community. I founded the company with @annalankauf to serve a mission to make the internet a better place. We stand behind many popular open source projects, like React Native. We fight for diversity, host workshops, teach others and speak at conferences.


We are passionate about what we do!

That’s why we teamed up with folks at Facebook, Airbnb and other companies to advance the web with the following projects:

React Native logo

React Native

We use React Native to write native apps of any kind with React and Javascript. Our developers, Mike (@grabbou) and Satya (@satya164), that are core team members, actively participate in its development.

React Navigation logo

React Navigation

React Navigation is the new navigation solution for apps written with React apps. Our developers, Mike (@grabbou) and Satya (@satya164) have contributed to it's development adding many features and improvements.

Expo logo


Expo is a great and fun way to develop React Native apps. We work with the Expo team to improve their tools and libraries. Recently we worked on Snack which provides a in-browser playground for React Native apps.


Your Direction, Our Code

Our mission at Callstack is to help you and your team deliver a better product.

That’s why working with us feels different than with other software houses you may find just around the corner.

No overheat of poor task management, delivery promises or time zone differences. We feel like your developers, just working remotely today.


We make sure your app is not only on the cutting edge, but rock solid in the long-term.

Always in Touch
Always in Touch

We're happy to use any software that you prefer, whether it's Slack, Asana, Trello, etc.

Pay as You Go
Pay as You Go

We are your very personal, full-time employees. Say goodbye to unrealistic quotes.

Hard to believe?

Check what our clients are saying

  • Mike Grabowski is one of the most talented developers I have ever worked with, and I will not hesitate to hire him again.

    Travis, CEO

    @Alexa top 100 site

  • We've been working with Callstack for 2 years now. So far it's been working great for us. Can't recommend more.

    Tom Frew, CEO


  • Working with CallStack has helped us complete several large projects and raise the developer IQ!

    Todd Williams


  • We worked with Callstack on our React Native app. Being half way around the world, they were very communicative and followed our technical instructions carefuly.

    Adeel Raza


We are 2 hours ahead of you! Based in Wroclaw, Poland, Europe

Get Started Now!

Send us your request and we’ll get back to you right away on how to get moving.

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