Interesting. Basically, this seems like a way to set up a dev environment with a set of packages that aren't installed globally on the system. Sort of like Python virtualenvs, but for any software package.

Could be very useful, but if it is actually aimed at developers (as opposed to sysadmins) and their workflows, it needs mechanisms to get and install software that doesn't necesarily go through the usual packaging workflow with all of its checks. If the scl equivalent of 'pip install Pillow' only gets the latest available official RPM, the utility to developers will be very limited.