Use Testcontainers to create a Docker Test Image

Tackle those long Liquibase/Flyway changelogs or setup your testdata from code!

TLDR?! You can always just check out the example on Github. Prerequisites: You should be familiar with JUnit, Testcontainers and have some fundamental Docker knowledge. I’ve seen a lot of projects use a database management tool like Flyway or Liquibase to update their databases. In production, only a small part of the changelog will need to run because most of the changes have already been applied in previous deployments. [Read More]

The Coffee 'Break' Conundrum

In IT: is it work time, or a break?

I’ve been hearing a lot of similar stories lately. They usually go like this: “Should I clock out of work if I take a small break? Technically I’m not being productive… so…" “You are getting a lot of coffee… and then you just stand there looking out the window. We don’t pay you for this." In this blog, I won’t talk about the regular Coffee Break Conundrums (Black or with milk? [Read More]

Host your own Map/Route Service API

The data is out there, you just need to expose it.

Route calculations… locally! For a recent project, we needed to calculate vehicle routes… a LOT of routes. We were using an optimization algorithm to plan delivery vehicle routes with multiple stops. Because the previous stop of a vehicle determines the start location of the vehicle for the next “delivery” and the sheer scale of the system, it did not seem practical to pre-calculate all the routes before running the optimization. So we decided to calculate routes while running the algorithm. [Read More]

Improving Twitter Card Visual

Improving my website - Part 1

In this series, I blog about the little ways I’m improving my website. Improving Twitter Card Visualization Recently, I saw a Tweet asking people to share their personal websites. As I have one (I guess…you’re here now… so… it counts!), I decided to share it. Twitter turned it into the following representation. 👇 I wasn’t happy with this at all! The image is small and not really adding value here (not even with my sparkling shiny self on it…); “Home” is the title of my homepage… not relevant for showing on Twitter; The summary is just the content of the page, but truncated to a limited text; As these were the defaults for my website… it was time for some investigation! [Read More]

Stakeholder[][] RACI = new Stakeholder[x][y]

Using a RACI matrix to map roles to stakeholders

More responsibilities I’ve been taking on more responsabilities within my company in the past year. 👊 Still programming and building cool stuff but I get to do other things like coach juniors, lead a developer community and organize events. It’s that last one which recently exposed a weakness of mine: Stakeholder management. 😕 The organization of the event seemed to go smoothly in my opinion. However as time progressed, it became apparent I was missing something. [Read More]

I failed a Java 11 Certification exam

Some basics I got wrong

So here is the deal. I am Java 8 certified. I have 8 years of professional Java experience. Without studying, I tried a Java 11 Certification mock exam… and only got 44%. 😕 Here are 3 basic questions I got horribly wrong. I have collapsed the answers per topic, so please do try to answer the question before looking at the answer. Overloading order What is the output of the following code example? [Read More]

Jumping into Kotlin

Early impressions

Early, but not an adopter 8 years ago, I was doing my internship at Info Support, my current employer. During that time, I got invited to join the rest of the team to my first meetup, the Visug Event April 2013. The main speaker that evening was Hadi Hariri developer advocate at Jetbrains. Hadi gave 2 talks that evening. The first was about the Silver Bullet Syndrome. The other talk was about this new programming language Jetbrains was working on. [Read More]

Back to presenting!

Picking up the pace again.

Phew… it’s been a while… I haven’t posted a lot of content on the website recently, days just seem to go by so fast when they all look the same. I’ve been very busy lately with giving talks and presentations at different schools. Some Selenium here, some Cucumber there, Testcontainers and Pact, Kotlin… all the good stuff! Now that most of the school lectures are over, I am once again going to focus on giving some presentations at meetups and conferences. [Read More]

Getting through the Q&A section of your presentation

Don't fear the Q&A... Embrace it!

Imagine being at a conference or meetup giving a talk. You completely ace it (I believe you will, even if you don’t, you badass!) but then you feel anxiety setting in. You can feel it coming for you, slowly, surely: the end of your talk. Which means… it’s time for Q&A: Questions and (hopefully) your Answers. Q&A is the most dreaded part of a presentation for some while being indispensable for others. [Read More]

Great stuff is Loom-ing on the Horizon for Java

A short look at Project Loom

Almost two years ago now, I was at Oracle Code One in San Francisco. It was there that I first heard about Project Loom, a project that would introduce some kind of new way to do concurreny in Java. At that point, Loom was just a concept, a promise to make concurrency in Java easier. Fast forward to today and Loom has changed quite a bit since that initial presentation. The time to catch up with Project Loom. [Read More]
Loom  Java  JDK