Launched “De Dolle Bool” (beta)

I have always wanted to create educational material to teach computer science concepts to children, as I feel there is room to improve on teaching those skills in the regular educational system. Now, I have launched a beta version of “De Dolle Bool”, a platform that attempts to teach various subjects to children through minigames.

Integrating Mollie in Netlify Functions for serverless payments

I have been a long time Netlify user and fan, mostly using it for static websites (like this blog). Recently however, I had a requirement to accept donations on a site I run and started looking for ways to do this. In this article I will describe the steps taken to implement Mollie payments on Netlify Functions for a fully serverless solution.

Playing with Log4Shell

As one of the most critical vulnerabilities of recent times, for which I had to patch some systems myself at work, I just had to learn more about the internals of CVE-2021-44228/CVE-2021-45046, better known as Log4Shell. It by no means is rocket science (in fact, it’s one of the most easily exploitable vulnerabilities of all time), but it still requires some work to setup a lab, figure out the right format of the exploit, etc.

A Yubikey for all your needs

Well, almost all, that is. A Yubikey is a great piece of hardware that supports PKI, OTP and U2F. It comes in various different models, some supporting NFC or even biometrics. They can all be attached to your (physical) keyring so it can always be brought along and they are nearly unbreakable.

My take on the OSCP exam

Although programming has been my area of professional focus for the past 20 years, security has always been one of my primary areas of research and experimentation in my spare time. The field requires both breadth and depth of knowledge and offers complex and exciting challenges.

Securing my network with a USG Pro part 1 - hardware

This two-part article is about how I installed and configured a Unifi Security Gateway Pro in my home network to make everything more secure and replace the ISP supplied hardware. It covers some inconveniences I encountered and some tips to mitigate them. The first part is a bit of a background story and also covers the installation of the hardware.

Automating your session logging

Whenever you need to be able to reproduce something from shell sessions, it can be very beneficial to have a full log of the input and output of your terminal session. The built-in tool ‘script’ can easily create a fully replayable transcript of your session that can easily be replayed with ‘scriptreplay’; this might be sufficient for some people in some cases.

Building a basic X86 kernel part 1 - Introduction

Welcome to the first part of a series of blog posts which serves as a tutorial on how to build a 32 bit protected mode kernel loaded by a 16 bit bootloader on the X86 architecture. While the resulting kernel will do nothing spectacular (in fact, it does nothing but print a message), the journey that leads to this result is what it’s all about.