minicoin
minicoin is a tool designed for building and testing Qt on multiple platforms, using virtual machines that run either locally, or in the cloud.
Documentation
For documentation of minicoin, see the project wiki.
Teaser
$ cd ~/qt5/qtbase
$ minicoin run build ubuntu2004
$ cd ~/my_project
$ minicoin run build ubuntu2004
This will first build qtbase from the local ~/qt5/qtbase directory on the ubuntu2004 box, and then build the project in ~/my_project on the same box, using the qtbase that was built just before.