So, I went "up to date" finally. I installed Debian 8 KDE and got Qt5. Good, I wanted to compile some projects. I choose a small database thing, which I would like to run ASAP. After some wrestling, I made Creator run and compile the thing.

(1) The app needs KZip, KArchiveEntry and some other zip-related classes. I know that this is the KArchive library now - but which library should I download and where shlould I get headers? Apper knows nothing about "KArchive". Google seems to be unusable here. I also have seen that I should add
Qt Code: 
  1. QT += KArchive
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but my Qt Creator knows nothing about "KArchive". libkdecore seems to exist in Qt5 but there is no "libkdecore5-dev" package in sight. Where are the headers?

(2) I also need "system fonts" (fixed and proportional fonts set by "system settings"). They were available at KGlobalSettings class from libkdeui in Wheezy. In Jessie, evil took libkdeui along with headers like kglobalsettings.h. How are system settings (fonts are enough) accesible now (in Jessie)?

What to do?