Sometimes you have packages that you don't use very often. You don't need them upgraded and installed every time you upgrade your system or user packages.
You can do:
guix environment --ad-hoc package -- program-to-launch
For example, I just did:
guix environment --ad-hoc krita -- krita
If you start to use a program more often, then you can decide to add it to your user/system profile!
That's currently the case with me and Krita... and maybe it'll become something I feel justified in having always around (I'd like that, actually... need more time to get comfortable in it)
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