This blog post <https://anarc.at/software/desktop/calibre/> popped up in my screensaver display a few minutes ago, and was interesting enough for me to find the original. Calibre is the well-known software package for viewing and managing ebooks and converting between formats. As the blog writer says: It's used by Linux geeks as well as Windows power-users and vastly surpasses any native app shipped by ebook manufacturers. I know almost exactly zero people that have an ebook reader that do *not* use Calibre. However, there seem to be quite a few problems with it, not the least of which is that the principal developer seems to have trouble appreciating security vulnerabilities. Another issue is that it is written in Python 2 (though an in-progress port to Python 3 seems to be mostly “going well”). At one point the developer claimed that wasn’t a big deal, as he could continue to maintain Python 2 himself after it became obsolete upstream, but he seems to have backtracked from that position. One pressing problem is that newer versions of Calibre depend on Python 2 libraries that are no longer available in Debian (and therefore would also disappear from all the usual Debian derivatives, like Ubuntu and Linux Mint). However, the list of useful functions that Calibre performs is remarkably long, so finding substitutes for them all is going to be rather daunting.