Callstack is a leading consultancy and development company founded in 2016 by Mike Grabowski and Anna Lankauf, specializing in cross-platform solutions using React.js and React Native. As core contributors to the Meta team, Callstack is dedicated to driving software development innovation and setting industry best practices. The company organizes the React Universe Conf, Europe's only community-driven conference focused on React Native, and offers opportunities for employees to work on impactful projects used by millions globally. With a strong emphasis on research and development, Callstack encourages its team members to explore new technologies and contribute to open-source projects, fostering a culture of collaboration and expertise.