Recent content on revontulet.dev
To install Arch Linux, the most common and easiest way is booting it up from an installation media. This may not be an option, and instead we want to install it straight onto a drive. The Arch Wiki provides a guide to Install Arch Linux from existing Linux , but it took a while to get all pieces right. Consider this post to aim for a more noob-friendly and handholding setup on how to install Arch…
Every year No Shave November and Movember are held to raise funds and spread awareness for Men’s Health, particularly cancer research and treatment. They are more or less the same, but not exactly. Movember vs No Shave November (tue.nl) provides a more detailed view of their differences. The idea is simple: Do not spend your money on a barber for the whole of November, instead donate it to a…
Since January 2023, I’m the owner of a Steam Deck. Until April 2025, my main computer still had Windows running, but I found that I hardly use it for anything but the browser and games. Given the Steam Deck experience, I was confident to ditch Windows and continue playing on Linux from here on. Especially as pretty much anything I play is on Steam. However, in my setup with an Nvidia RTX…
Here’s a short one about a pattern that we can unfortunately too often observe when it comes to mocks. Especially with databases, we see our “Repository” or “Database Connection” mocked out in tests. That is, for the sake of unhappy path testing. However, more often than not we also see that these mocks are used for happy path testing. There is a real danger where our…
This post has been lying around as an idea for a couple of months now. A list of bullet points on my computer is from somewhere mid-June, and I originally intended to title it “The Underappreciation of Fast Feedback Loops” . However, calling out a cost sounds catchier and is more accurate, because we do not only underappreciate them, but they cost us. First and foremost, nerves…
The Matrix AI is everywhere. It is all around us. Even now, in this very room. You can see it when you look out your window something up on the internet or when you turn on your television washing machine . You can feel it when you go to work do anything nowadays … when you go to church a search engine … when you pay fill out your taxes. It is the world that has been pulled over your…
This post covers how to tether your iPhone via USB to your RaspberryPi, and share the iPhone’s network on eth0 . Eventually, the RaspberryPi will be connected to a router via ethernet, making the router use the iPhone’s internet connection. A RaspberryPi 4B is used, but this guide should work on other models too. One may wonder why this setup is needed. Routing at least DNS traffic…
Welcome to part one of the three-part series “Hello, Sway!” The series is split into Arch & Sway setup using archinstall Sway Configuration Linux QoL Tools Motivation For a while already, there has been no real reason for me to keep Windows. The doubt started about two years ago, in January 2023, when I got myself a Steam Deck. Although the purchase was mostly to emulate console and…
Welcome to revontulet.dev! So … what is this about? Introduction My name is Matthias Döpmann. I’m a Software Engineer, originally from Germany, nowadays located at the Arctic Circle in Finland. There is no specific content for this blog. At the time of writing, I host a couple of articles on MisterDerpie.com , that I intend to migrate over to this blog. There were several reasons I…
To be populated :-)
Using i3 and Ubuntu native is probably best, but you may not get the choice to do so, in case your working machine is running Windows. I looked through several guides how to set up Ubuntu with i3 on WSL2, but it took me several hours to get the setup I looked for because things did not work as expected. Therefore I’m writing this guide. Installing Ubuntu on WSL2 There are plenty of tutorials…
During my summer vacation, I got myself a Lenovo Legion 5 Pro, powered by an AMD Ryzen 7 5800H and an Nvidia RTX3070. Though this post is not about the legion, I have to say it is an awesome laptop. What this post is about is how to make Ubuntu with i3wm run on the Lenovo Legion. Installing Ubuntu Create Bootable USB Media You need a USB stick as well as a Ubuntu ISO image. Plenty of tutorials…
In my previous post I stated that I am currently reading Kotlin in Action (2017, Manning). In chapter 9, the authors introduce generics in Kotlin. My overall experience with generics in Java is good, but apparently that book taught me something completely new. The concept of Covariance and Contravariance was something unknown to me. This post, though categorized Kotlin, focuses more on the…
The repository with the Kotlin code can be found on github/MisterDerpie/kotlin-data-stubs . Currently I’m having the great luck that our team started using Kotlin at work. For that reason, I decided to learn Kotlin properly and started my journey with Kotlin in Action (2017, Manning). This is a bit outdated, considering that Kotlin 1.5 is the current release, but the vast majority of…
The sourcecode of this post is available on github/MisterDerpie/spring-boot-with-mongodb . Foreword For a small application to store receipts I wanted to use Spring Boot and NoSQL database MongoDB . As with many basic topics in the spring world, there is a Getting Started guide on spring.io , with the specific title “Accessing Data with MongoDB”. Though this guide may suffice for a…
Foreword Since many years I am using JDownloader as the solution to download things on all my computers. The problem with it is though that the files are not synchronized between them. Thus I cannot access what I downloaded from any machine different from the original downloader. This problem worsens even with the fact that once I am not at home, I cannot access the harddrives the multimedia is…
Foreword This blog is created using Jekyll . The striked through sentence above used to be true for the old version of this blog, hosted on [misterderpie.com]. However, the version at [revontulet.dev] uses GitHub pages and Hugo. Original Post I really like Jekyll, as I don’t like frontend development. One problem is though, that I currently only have Jekyll installed on one single machine.…
In my previous post, I showed how to enable the Raspberry Pi 4 on Ubuntu Server to read out DHT11/DHT22 sensor data. But this is a very hacky solution. Moreover is the Raspberry Pi cluttered with some stuff, that we may need to configure differently for another setup or remove as a whole. It’s a nice coincidence that I’m currently reading Docker in Action, Second Edition (Manning,…
I recently bought a RaspberryPi 4 and installed Ubuntu Server 20.04 64 Bit on it. There are many tutorials available how to read the temperature/humidity via Python, unfortunately none of them worked out of the box. It seems to be that they are either for Raspbian OS or for 32 Bit OSes. After some searching I found a way from several sources to make it run. This is a horrible hacky workaround and…