DON'T HACK THE PLATFORM ☠️💣💥

In 2022, Jan presented his tricks to hack the Java platform at Devoxx Belgium and created awareness of some of the lesser-known vulnerabilties of Java and the JVM.
Watch the talk...Building a Bullsh*t Language

I have created AnnotationScript, a programming language whose syntax is expressed entirely in Java annotations. Yes, you read that right: Java annotations. WTF!? The pandemic lockdowns of 2020 did strange things to people. Some people started learning the guitar. Others decided to get in shape. But not me. I decided to take Java annotations to their logical extreme. I think annotations are over-used in the Java ecosystem: you can use them for dependency injection, handling HTTP requests, and interacting with databases. You can even use them to generate code in various ways. But for some reason, nobody has actually used them to implement a full-blown, Turing-complete programming language. Until now. Do you want to know about the weird restrictions that Java annotations have? Do you want to know how you can still abuse them to do something weird like this? Also, do you want to know how easy it is to actually implement LISP? And do you want to know how easy it is to recursively implement LISP in the LISP you just implemented? You will be amazed. Weirded-out and amazed.
Watch the talk...Just enough Computer Science for the busy developer

A CS degree is not a requirement for software developer roles. Nor should it be! I have worked with biologists, psychologists, and even a historian, who all were excellent coders. And that's great! Diversity of thought leads to better software, after all. Still, there are some super useful CS fundamentals that will make you a better programmer, but that you may not pick up on the job. This talk gives an overview of some of these fundamentals, such as De Morgan's Laws, the Big O notation, and how algorithm complexity informs whether you should use an ArrayList or something else. It also introduces you to the remarkable people who came up with these things. They ended wars, sent rockets to the moon, and were made into Lego minifigs. Who said computer science is boring?
Watch the talk...Pitfalls and Practical Solutions

At AxonIQ's 2020 conference, Jan-Hendrik presented his talk Pitfalls and Practical Solutions. It discusses real world issues with building and maintaining an Event Sourcing application.
Watch the talk...Exploring Sustainability in Tech Without the Guilt-Trips
Most of us are all well aware of it: the current trend of climate change is not looking great. We can already feel some of its consequences and it is very likely to only become worse. As software developers we’re all about innovation though, so as long as we’re innovating not all hope is lost. So how can you use innovation to become more sustainable, both as a software developer and as a human being? There is no single answer to that question, which is why we’re hosting this talk as a panel so that you’ll be able to hear multiple opinions. Each of us has a different perspective and knows different things we can do to help make a difference, and we'd like to hear from you as well! We’d like to emphasize that we don’t want to guilt-trip anyone. This session is intended as a source of inspiration. The sheer scope of the problem can cause even the best of us to freeze up. Hearing ideas, no matter how small, from peers will provide you and us with ideas for the next step to take. This talk could be an opportunity for you to catch a few sustainability tips that can find their way into your life without costing you any noticeable effort.
Watch the talk...Master Your Tools

A laptop is to a developer what a toolbox is to a carpenter. This talk showcases ways to speed up a dev's workflow and inspires you to learn about the tools at your finger tips.
Watch the talk...The Case Against Framework

Another day, another silver bullet. The world of software development changes so rapidly and with every new framework, there will be those that claim it to be the solution to all your problems.
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