Thoughtpile I write things here.

Set up UnifiedPush with Matrix support in Gentoo

I set up UnifiedPush because I wanted push notifications in FluffyChat without talking to Google. This was a bit more difficult than I imagined, so I’m writing it down here. I will go into Gentoo specifics but a lot of this article should be useful for other Linux distributions and operating systems as well. UnifiedPush works like this: You have a server and a notification-application on your phone. The notification-application connects to the server and receives push notifications from it.

Control Group version 2 by hand

We have Control Group v2 since 2016 but I had trouble finding good documentation on how to use it. Most tutorials and blog posts only cover v1 or are specific to systemd[1]. The kernel documentation is a great reference and the basis for this post but not always easy to follow. I will give you a few short examples on how to use it. I will not explain everything, but hopefully enough to get an idea and understand the reference better.

Meta: This blog is multi-language now

I will begin publishing posts in German on this blog. The default RSS feed will contain only English posts. The German RSS feed will contain only German posts. So if you want to get posts in both languages, you will need to subscribe to both. I am not sure yet if I will translate new posts to both languages. Probably some posts will be only available in English while others will be only available in German.

Meta: computering and thoughtpile merged

Hi, I just merged into It doesn’t really make sense for me to keep 2 blogs with my low posting frequency and there wasn’t really that big of a difference between the two. Your RSS readers should handle the move automatically for you. Subscribers of computering: Your RSS reader will probably show you old posts as new. That has technical reasons resulting from the domain change (The GUID contains the URL) and I can’t do anything about it, sorry.

How I convert PDFs to EPUB semi-automatically

Sometimes e-books come only in PDF format. Almost always PDFs are a pain to read on e-book readers. You can use Calibre to automatically convert it, but the results are okay-ish at best. If the PDF has footnotes, forget it. Unfortunately, the type of books that most often come only as PDFs are science books and these usually have a lot of footnotes. One option is to use Calibre to convert and then fix the result, but I have found that I get better results in less time when I create a new EPUB, copy the PDF’s content into Emacs, clean it up there and then copy it over to Calibre.