Recently, Matt pointed out that profile collisions can be confusing and difficult to resolve:
https://lists.gnu.org/archive/html/guix-devel/2022-01/msg00115.html Specifically see this blog post: http://excalamus.com/2021-10-06-guix-debug.html I think we should add a Cookbook chapter on the subject. This particular error state seems unavoidable given the size of the distro and the number of packages that use propagation. So, let's help users understand it and give them the knowledge to even help resolve such collisions as contributors. Speaking as somebody who understands intimately what a profile is, what propagated inputs are, and how they can interact to cause "profile contains conflicting entries", I am sympathetic. Although I know exactly how to resolve such errors, I have also explained the situation to new Guix users several times on IRC. Many people come to Guix, install some packages, use them, then want to upgrade them, and they have never learned what a profile is or how it is the fundamental mechanism by which Guix implements package management. It also seems to me that plenty of people would prefer not to ask for help, but rather go searching online and in the documentation, which does not include the string "contains conflicting entries". I envision a Cookbook chapter that explains what a profile is, what propagation does, what profile generations are, and then how they all combine to cause this error state. And an example of a resolution, whether by adjusting a package definition, uninstalling a package, etc. There are some older Guix presentation videos that I think do a great job of explaining profiles and generations, including slides with good illustrations of the subject. It would be nice to try using that style of illustration, as I found it clear and illuminating when I first learned about Guix.
