Well, the issue seems to be with the commit that adds the transformed polybar package like this:
```
(define-module (zero packages polybar))
(use-modules (guix packages)
(guix transformations)
(gnu packages wm))
(define-public
polybar-3.7.1
((options->transformation
'((with-version . "polybar=3.7.1"))) polybar))
```
