Matthias Keiser

I'm a software developer from Switzerland (iOS, OS X macOS, POSIX, JS, web). I'm working on the awesome Sketch image editor by Bohemian Coding. I served as Chief Product Officer for a start-up that just made Entrepreneur's 360™ list. If you ever played a mobile video with VLC, you have probably run code I wrote.


Tristan Inc. currently sells one app:


FSMonitor is a macOS app that monitors all changes in the file system. Learn more.

Open Source


I contribute to the VLC media player. I'm the author of the CoreAudio demuxer module. I also contributed a series of patches to correctly handle rotated videos (as produced by i.e. iPhones). It made the VLC maintainer happy.


A swift module that makes it more convenient to work with Universal Type Identifiers. It's available on GitHub and CocoaPods.

Swift BinarySearch

Native binary search is curiously missing from the Swift standard library. I released a module that fills in that omission. It's available on GitHub and CocoaPods.


I released a small iOS component that implements a tab view as seen in Mobile Safari. It is very flexible and uses an intuitive API thats inspired by iOS' UITableViewSource. It's available on GitHub and CocoaPods.


Matthias Keiser

twitter: @mtthsksr