Here you find an overview of my work during the last twentyfive years. I have written millions of lines of code, created countless designs and trained so many people, it would be too much too list everything. What follows is a summary of the projects I am most proud of in my career.

2020-today Python for everyone

I offer a variety of online Python courses where I teach beginners how to create their first programs and help professionals how to understand Python better.

Python Training

More info can be found on my online training website

The feedback I get from my students is that the courses are well structured, with lot’s of practical examples, they had a lot of fun during the training and it convinced them that programming at any level, is not magic, but a learnable skill

2019-today Aliens Bring Change

In 2019 I started a game studio in Berlin. I make games for KaiOS and Windows 10. Among the titles are Mahjong Solitaire, Solitaire Battleships, Solitaire Cards, Memory and many others.

KaiOS Games

Windows Store Games

Aliens Bring Change Game Studio

2017-2019 Microsoft Mixed Reality Studio

As Senior Software Engineer for the Microsoft Mixed Reality Studio in Berlin, I created Holographic Applications for Hololens for our customers in Germany. For Toyota Material Handling, I programmed the application flow for a Holographic Warehouse Simulation, demonstrated here by Satya Nadella, the CEO of Microsoft:

Satya Nadella

Hololens for games

The Hololens is also a fantastic gaming device. The following video is of a hobby project I created in my spare time. I use my XBOX controller to move a holographic fish through the office:

Hololens Studio

Public speaker

I speak at conferences like Microsoft Bootcamp Amsterdam, Technical Summit Darmstadt, MVP Seattle, GUI an Design conference Berlin, DWX Developer week Nürnberg, Spartakiade Berlin, Developer Open space Leipzig.

Loek at Microsoft technical summit

2015-2017 Microsoft Todo

Microsoft To-do, the sucessor of Wunderlist, built to integrate with and use Exchange Online.

Microsoft Todo

Wunderlist had a huge fan base and in 2016 it was officially replaced with Microsoft Todo. Imagine my surprise when I saw my own app on the news in the Berlin subway.

Microsoft Todo

2013-2015 Wunderlist

Wunderlist for Windows 10 was built between 2015 and 2016 and runs on tablets, laptops and Windows Phones. It is part of a large family of apps that run on Windows, iOS, Android and the web.

Wunderlist 10

When Microsofts CEO Satya Nadella was asked about his favourite app on his homescreen, he made us very proud by saying it was Wunderlist

Wunderlins on Satya Nadellas Phone

Wunderlist for Windows 8 was built between 2013 and 2015 and runs on tablets, laptops and Windows Phones. The prototype below was created for Windows 8 tablets.

Wunderlist 8

File Commander (2012-2014)

Filecommander is a Universal Windows file manager that allows you to organize files from tablets, phones and laptops.


File commander

2004-2013 Toverstudio

Between 2004 and 2013 I worked as a freelance Trainer and Software Engineer. Here is an overview of the projects that I’m very proud of.

Coming soon

1999-2004 Atos Origin

Coming soon

1998-1998 Via

Coming soon

1995-1997 DLoG GmbH

Fresh out of the army, I started my first real job in Januari 1995. DLoG created hardware and software for drilling and milling machines. I installed our software and trained machine operators in The Netherlands, Belgium, Germany and Poland.

A big part of my work was writing interfaces (post processors) between our software and factory machines. Here you see a drawing that is converted to machine instructions for a specific milling machine.


The software was created in Olching, Germany. I created the dutch translations, designed icons and screens. First for DOS, then for Windows.


Alles nur Mathematik (It's all just math)

Me, teaching customers how to operate the CAD/CAM software.