I used to develop whole applications, even full-stack. However, as Free and Open Source (FOSS) is becoming more common, I'm shifting to releasing specific technologies and contributing to existing systems. Below is a list of open source products that I have released or that I am contributing to.

Web Application Task Engines

These are applications for running reaction time tasks in a web browser, so that they can be deployed on desktops, laptops, smartphones, and tablets. I'm contributing to lab.js and jsPsych. For the latter, check out my jsPsych bundler. I'm disbanding my own JASMIN and recycling technologies it contained that are still useful. JASMIN (1) is compatible on touchscreen and keyboard devices, (2) is multi-lingual with procedurally generated instructions, and (3) has tasks that could be configured via forms. See a JASMIN demo.


Database breaches are one of the most common security breaches out there. By storing data in an encrypted format, it is protected against such breaches. I like to encrypt via Libsodium, because it is a well-established library with bindings for a large number of programming languages. See examples of Libsodium for JavaScript, PHP, Python, and R, over here.

Patching JSON

JavaScript Object Notation (JSON) has become the serialization standard of the Internet. All kinds of other standards are popping up around it as well, such as JSON Schemas. Another set of standards describe how to modify an existing JSON data structure. I like JSON Patch, but it's a bit limited when adding objects or arrays, so I invented the JSON_patch_each extension.


R is a powerful programming language for statistical analyses and machine learning. I think that in time it will be supplanted by Python, because the latter is a more general-purpose language. But not yet... Watch this space to discover my first R package soon!

This Website

It uses Boostrap 4 as CSS framework and CodeIgniter as PHP framework.