Before this commit it was possible to build a guix home configuration where home-environment-variables-service-type could ungexp any file-like object such as a package. The commit 73684dc90 forces it to be a string, which contradicts the documentation for guix.
Concretely, guix home environment test-home.scm worked before that commit where test-home.scm is attached to this email. -- Regards, Kabelo M'sobomvu Moiloa
(use-modules (guix gexp) (gnu home) (gnu home services) (gnu packages base) (gnu services)) (home-environment (services (list (simple-service 'add-environment-variable home-environment-variables-service-type `(("PACKAGE" . ,(file-append hello "/bin/hello")))))))