Journal on Johannes Karl Arnold

Setting up a Matrix Homeserver on NixOS (Easy Edition)

Fri, 15 Aug 2025 22:50:57 +0200

How I set up my own Homeserver

On using `uutils`

Fri, 21 Mar 2025 13:23:56 +0100

Beginning with commit 879f3af in January 2025, I have been using uutils on my NixOS machines.

Uutils is a Rust rewrite of the GNU coreutils and the experience has been nothing but wonderful. I’ve encountered zero bugs, and everything is snappy.¹

How to enable it? #

For NixOS, the process is quite easy. You can simply add the non-prefixed versions to your system’s packages. These binaries are then used in place of the GNU coreutils:

systemd-homed first impressions

Sun, 23 Feb 2025 13:26:29 +0100

One of the priviliges of starting my new job is that I am issued a laptop with the freedom of installing any distro I like. Usually, this process is a no-brainer — I pull out my trusty NixOS boot stick, format the drive as bcachefs & install, and git clone my configuration with which I rebuild the system to my preferences. Easy, right?

Now, a company laptop isn’t the same as my other, single-user laptops;

OpenWRT Meshing

Sat, 08 Feb 2025 14:58:04 +0100

After moving to a new, larger apartment, I had a problem: the office had a terrible Wi-Fi connection, and the office was so far away from our DSL gateway that laying a long ethernet cable was out of the question. Fortunately, during a trip to the USA, I found something I couldn’t pass up: a TP-Link Archer A7¹ at Goodwill for a whopping $6.99.

For less than the price of a fast food meal

The router immediately stood out to me, as I have used the extemely similar Archer C7 v5 since 2020. The machines are not only alike in appearance, but also on a hardware-level: both share the QCA956X CPU, 16 MiB flash storage, 128 MiB RAM, and of course the same wireless chipsets. Apparently, the A7 featured IFTTT and Alexa integration, resulting in some minor revisions and necessitation a slightly differnt OpenWRT firmware.

Building an Outdoor Meshtastic Solar Node

Mon, 29 Apr 2024 00:00:00 +0000

Meshtastic has taken off in my hometown. After my first post detailing the build of my first Meshtastic node and chatting with new users in the area, I decided to continue “investing” into our network, especially as I live in a high-rise apartment with access to outdoor stairwells, I have an excellent line of sight view of the city.

Assembly #

There are quite a few awesome solar nodes on Reddit, many of them hacked into the enclosures of solar-powered outdoor LED lights. While many of these probably function and look fine, I’ll be honest: I didn’t want to take the risk that the solar panel or batteries couldn’t power the node long-term. I’d rather spend a little more money for a purpose-built case than possible have to hunt down and gut parts of questionable quality.

My first Meshtastic Node is now Online!

Wed, 27 Mar 2024 00:00:00 +0000

I believe the first time I head of Meshtastic was during the COVID pandemic, probably through one of Andreas Spiess’ videos. I thought the Idea was neat (I was deeply into DIY electronics then as I am now), but I quickly decided the project wasn’t for me. I wasn’t aware of LoRa’s range nor did I have the money as a broke college student to go out and build a transciever with no other people to talk to.

Glycine GL0388 -- Cheap Homage or a Modern Classic?

Wed, 29 Nov 2023 08:33:44 +0100

It started with Black Friday Curiosity #

One cool evening in mid November I decided to head back to Drop.com. Considering my new job and the upcoming black Friday deals I figured it would be the perfect time to check up on my once¹ beloved drop-shipping site. It was here that a watch caught my eye: the Drop + Glycine Combat Sub “Soda”, pictured below.

Fixing Silverblue Permissions

Sat, 09 Sep 2023 12:51:09 +0200

Fixing an annoying issue with logrotate

How Sudoku saved an Experiment

Tue, 16 May 2023 00:00:00 +0000

Theoretical CS has its real-life applications after all

WPA3 Troubles

Tue, 29 Jun 2021 00:00:00 +0000

Addressing a WPA3 Bug with OpenWRT and Linux

Initial Commit

Wed, 31 Mar 2021 16:19:01 +0200

My first blog post