The latest Debian package qualcoder-1.4.deb is available from https://github.com/ccbogel/QualCoder-Debians
This is for easy instillation on Debian based Linux systems such as Debian, Ubuntu and Linux Mint.
It may not be standards compliant but it works. It creates an application launcher or you can run it from the terminal via the following command:
python3 /usr/share/qualcoder/qualcoder.py
Post updated 27 Oct 2019
QualCoder 
As a Debian user, thank you. Do you think there would be any chance for a flatpak in the future?
Hi, The latest deb package (1.3) is quite old now. So I would not recommend. I will try and make a new one. What system do you use? Ubuntu? I have looked at flatpak – but it is too hard to follow.
I have updated the debian package see the 1.4 version now.