About Me

Hi, I'm Witek - an iOS developer based in Kraków, Poland. I'm currently working as iOS Lead at Stoic, a Y Combinator-backed mental health app with over 3 million users worldwide.

What I Do

I specialize in iOS and Apple platform development, with a deep focus on Swift and building intuitive, performant mobile applications. With a Master's degree in Computer Science, I bring both academic rigor and practical experience to my work. I'm passionate about creating tools that improve people's lives, whether through mental wellness apps or developer productivity tools. As a two-time WWDC Scholar (2018 & 2019), I was awarded the opportunity to attend Apple's developer conference as a student for my iOS development projects.

Technologies & Skills

Languages & Tools

  • Swift
  • Agentic Coding
  • Xcode & Xcode Cloud
  • TestFlight
  • App Store Connect

Platforms

  • iOS
  • iPadOS
  • macOS
  • watchOS
  • visionOS

Frameworks

  • SwiftUI & UIKit
  • Core Data & CloudKit
  • HealthKit & Screen Time API
  • StoreKit & RevenueCat
  • XCTest & Swift Testing

Open Source

I've created several open source libraries, with my most popular project being EPUBKit - a Swift library for parsing EPUB documents with over 290 stars on GitHub. I also built developer tools like vim-swiftdocstring to enhance Swift development workflows.

Beyond Code

When I'm not coding, I'm a passionate runner, climber, and backcountry skier - often accompanied by my three dogs. You can track my activities on Strava, see what I'm reading on Goodreads, or find me answering questions on Stack Overflow. I'm always curious about learning new things and sharing knowledge with fellow developers.

Get in Touch

Feel free to reach out if you want to collaborate on a project, have a question, or just want to say hi. You can find me on GitHub, Twitter, or send me an email.

Witek working with laptop and dog