Boudewijn Rempt, a Krita developer, writes about KDE, Qt, Linux desktop software, and open source development.
Commenters call his post on Qt offering changes excellent, and cite his Qt4-to-Qt5 porting account for Krita.
Krita was started in 1999, only four years after GIMP. For most of their existence, these two programs have been developed in parallel.
http://slangkamp.wordpress.com/2009/05/23/10-years-of-krita/
http://www.valdyas.org/fading/index.cgi/kde/krita_10_years.html
Part of the reason Krita development has accelerated massively in the last couple of years is that its team decided on a clear mission statement at some point, one very different from GIMP: Krita is a painting app first. The main use cases are painting, illustration and texture-making. That it's also quite useful for cases GIMP traditionally aims at (photo editing, web graphics) are down to toolset overlap between the use cases and a robust, modern tech foundation (colorspace-independent implementation strategies, etc.), but Krita isn't actually trying to compete with GIMP and ventures into territory GIMP doesn't really serve.
> As for Krita, we’re using Qt 5.12 for our binaries because we carry a lot of patches that would need porting to Qt 5.13 or 5.14 and because Qt 5.13 turned out to be very, very buggy. For Krita, using a stable version of Qt that gets bug fixes is pretty important, and that will be a problem, because we will lose access to those versions.
https://valdyas.org/fading/software/about-qt-offering-changes-2020/
You need a LTS of some kind if latest version is buggy as hell.
It didn't get any traction on HN at the time, but I thought the following blog post about Qt offering changes, from a long-time Qt user, was excellent:
https://valdyas.org/fading/software/about-qt-offering-changes-2020/
HN thread: https://news.ycombinator.com/item?id=22177821
Wanted to add this link by a Krita developer describing their experience porting from Qt4 to Qt5 - http://www.valdyas.org/fading/index.cgi/2015/04/06#portingkritaqt5
Meh. Pikers. Our campaign started in 1992, with a home-grown system -- https://valdyas.org/aurea.html -- and it hasn't ended yet. Though we've got a lot of arcs.
Another KDE developer (famous for Krita painting app) shares his thoughts aboout this: https://valdyas.org/fading/software/about-qt-offering-changes-2020/