Development on Maarten on IT

Building a CLI with Quarkus, Kotlin and GraalVM

Mon, 28 Jul 2025 08:17:00 +0200

Command-line tools are great for automation, but choosing the right technology stack to build them can be tricky. I recently set out to build a new command-line application to streamline some tasks, drawing from previous experiences where the tooling left me wanting more.

This time, I chose a different combination of technologies that better suits my needs: Kotlin, Quarkus, and GraalVM. In this blog, I’ll walk you through the setup and decisions behind this stack—so you can get up and running even faster when building your own CLI tools.

Measure Your Maven Build

Fri, 15 Mar 2024 09:46:00 +0200

Slow builds are annoying!

There, I’ve said it. And you know it’s true, don’t you? They take valuable time, they are a source of frustration, they extend the feedback cycle, and often they provide the perfect excuse for slacking off.

But it doesn’t have to be this way! Rather than getting another cup of coffee or playing that medieval game of gladiator, what if we would investigate why the build is so slow? If we know the bottlenecks, we can address them. That would shorten the feedback loop, increasing our productivity and our job happiness in one go.

Use git bisect to pinpoint a bug

Thu, 28 Jan 2021 14:15:09 +0100

During my work on Maven today, I found a very specific bug. The error message wasn’t that clear, and I couldn’t make a guess what might’ve caused it. I read about git bisect a few times and figured that today, I would use that tool to find the bug.

What's New in Maven 4

Mon, 30 Nov 2020 08:02:09 +0100

Recently, the Maven community decided to push forward and start working towards a 4.0.0 release. The first question after this announcement is of course: what can we expect Maven 4 to bring us? A lot - and in this post, we want to highlight some of the features that we are particularly excited about.

Multiple Git identities

Mon, 13 Jul 2020 08:10:05 +0200

Everything is code, and code is everywhere. For me, this means I put more and more stuff into version control. Whether it is infrastructure descriptions, documentation, software or this blog, I always store it in a Git repository. But sometimes this gets dirty, because you accidentally forget to change your Git user details.

DevNexus Day 2: Metrics, Monolith Decomposition

Fri, 21 Feb 2020 21:55:00 +0200

Together with four “AwesomeSauce” colleagues from Info Support, I’m attending DevNexus this year. For me, it’s the second time I’m here, as I spoke here in 2018, too. Next to delivering my own “React in 50 minutes” session I’m attending some sessions to update with new technology advancements. After a great first day, let’s move on to the second (and last) day.

DevNexus Day 1: WebAssembly, Productivity

Fri, 21 Feb 2020 15:20:13 +0200

Customise the Maven Release process

Fri, 10 Jan 2020 09:30:13 +0200

Shipping a new release of software usually involves quite a few steps. Depending on the type of software, this may be something you rarely do. Thus, it often involves manual steps. This is not necessary! Maven has had its “Release Plugin” since approximately April 2007; yes, that’s over 12 years! It has served both the Maven project and many other software projects.

Devoxx - Day One

Wed, 06 Nov 2019 17:22:13 +0200

This year I’m returning to Devoxx. I’m planning to write some notes on interesting sessions or other content. Also, I’ll be delivering my talk on Transport Layer Security tomorrow. But today was a day of catching up with old friends and attending a talk or two.

One talk really caught my attention: “Implementing a simple JVM in Rust”.

Building a programming language on GraalVM (Part 1)

Sun, 13 Oct 2019 16:27:13 +0200

If you’ve followed recent developments in the Java ecosystem, you must know GraalVM. Many blog posts cover how you can build native executables from Java source code. This is indeed exciting: your program starts faster, and consumes less memory. Other popular topics include building Java applications that run code in other languages. You can run JavaScript, Python, Ruby or R code in the JVM. But there’s more: in fact you can run any language inside the JVM! Are you curious how? Continue reading…

Code One - Day Three

Wed, 18 Sep 2019 20:08:00 -0700

Third day on Code One already! Highlights for today: the Community Keynote, a trip to GitHub and a session called “Sarcasm as a Service”.

Code One - Day Two

Tue, 17 Sep 2019 16:11:00 -0700

On this second day at Code One I have again visited interesting sessions. One on security by Jim Manicode and one on cash (or the lack thereof) in Sweden.

Code One - Day One

Mon, 16 Sep 2019 18:42:32 -0700

This year I’m returning to Oracle Code One (formerly JavaOne) for the third time. I’m planning to write some notes on interesting sessions or other content.

How did I get that library?!

Wed, 11 Sep 2019 18:42:32 +0200

When you’re writing Java applications, chances are you’re using Maven for dependency management. It lets you declare the artifacts you need to build your application. Those artifacts also depend on other artifacts. This means you have transitive dependencies - dependencies you didn’t declare yourself but you need them anyway.

Troubleshooting SOAP and MTOM using the command line

Mon, 17 Dec 2018 09:24:13 +0200

When you want to transmit binary files over SOAP-based webservices, you have two choices: Base64 or Message Transmission Optimization Mechanism (MTOM). The latter is much more efficient, but also harder to troubleshoot if it doesn’t work at once.

Both options have their own typical scenario

Serialise the file content using Base64 and include the result right into the XML structure. This is relatevely easy to implement and troubleshoot. It usually works well for small binary files, but as files grow larger, you may run into performance issues. The Base64-encoded binary file may be so big that the XML parser will blow up.
Use MTOM to transfer the request and attachments. In this approach, the SOAP request (XML) and any attachments are sent as a multipart request. This is a bit harder to implement, and if it doesn’t work at once, it is even harder to troubleshoot. But on the other hand, it allows for much more efficient transportation of the attached files.

SOAP over HTTP

As a primer, let’s have a quick look at how “regular” SOAP requests look when transmitted over HTTP. Imagine we have a file upload webservice which accepts files in any format, along with a file name. If we were to upload a file, the request might look like this.

A first look at MVC 1.0

Fri, 14 Sep 2018 21:20:19 +0200

Recently, Twitter brought the renaming of Ozark to Krazo to my attention. It pulled my attention: I had never heard of either projects, and I wondered what they would be about. Ozark (or Krazo) will be the Reference Implementation of the new Model-View-Controller Specification. This MVC specification, also known as JSR 371, was planned for inclusion in Java EE 8, but eventually dropped. Apparently, this didn’t kill the effort. I was curious to see where the specification (and it’s implementation) would be now.

Custom SOAP Faults using Spring WS

Tue, 24 Jul 2018 16:05:35 +0200

There are many situations when you need to write a SOAP-based webservice. Maybe you are writing a test dummy, or maybe you got the interface from some kind of architect. (Yes, there are other reasons, too.) And chances are you’ll be using Spring-WS to do this.

Recently I was doing that, and I found the following inside the interface definition (WSDL):

<element name="faultMessage" type="common:FaultMessage"/>

<message name="faultMessage">
 <part name="faultMessage" element="tns:faultMessage"/>
</message>

<portType name="someName">
 <operation name="searchOrder">
 <input message="tns:searchOrderRequest"/>
 <output message="tns:searchOrderResponse"/>
 <fault name="faultMessage" message="tns:faultMessage"/>
 </operation>
</portType>

That was a rather challenging thing! In case the operation would fail, it should give a SOAP Fault with a custom element in it:

Building ASP.NET Core apps on CircleCI

Mon, 02 Apr 2018 11:42:35 +0200

Recently, my co-worker Willem pulled my attention to the .NET Microservices. Architecture for Containerized .NET Applications e-book. Although I have a strong background in Java and the Java platform, I started reading it, and soon I felt like trying it out. But building software without having automated builds and tests is not the real thing, so that was the first thing I wanted to do. I usually use CircleCI for that, but unfortunately they don’t seem to have an official guide for that.

Quickly count your code base

Wed, 03 Feb 2016 08:10:40 +0200

Often, the size of a code base is measured in terms of “source lines of code” (SLoC). If you’re interested in the size of your code base - or your client is - this metric provides a way to express that size. Of course, comments and the like are not considered to be code, so how to determine this metric? Using grep is tempting, but it quickly results in a very complex and hard-to-understand approach.