Marcin Leon Omelan

Hi, I'm Leon ๐Ÿ‘‹๐Ÿป

I'm a software engineer based in Toruล„, Poland. I'm passionate about bringing the best possible apps to all platforms. I believe that the best apps are the ones that are fast, accessible and easy to use, and one that follow given platforms design guidelines, and sensibilites.
I have over 7 years of experience in software development, and delivering high quality software.
In my free time I work on my open source passion project Cofi . It's a simple, and easy to use coffee timer app that helps you brew delicious coffee at home.

I'm currently working at Callstack as a Senior Software Engineer. Where I'm responsible for developing high-quality software, that is used by milions of users every month.

Work Experience
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  • Oct2024 - current
    Callstack.io
    Senior Software Engineer
  • Feb2018 - Oct2024
    Nozbe sp. z.o.o
    Software Engineer
    • Worked with ReactJS and React Native to build cross-platform productivity application that has feature parity across all platforms.
    • Built developer tools, automation scripts, CI/CD pipelines and more.
    • Worked on WatermelonDB as one of the main contributors to create one of the fastest ways of storing and retrieving data in React world.
    • Worked hand in hand with the design and customer support teams to design and develop features that would bring new users to the app.
    • Had a hand in planing and executing A/B tests across the app to optimize user retention and acquisition
Recent projects
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Let's Connect

If you want to get in touch with me about something or just to say hi, reach out on social media or send me an email.