Good news for declarative config fans: finally there’s a #Guix System service to deploy home environments!
https://guix.gnu.org/manual/devel/en/html_node/Guix-Services.html#Guix-Home-Service

Thanks to Richard Sent for implementing it, based on code by nostr:npub1zglpd69ltamxe7nnm6rdfleu8amgg3sn24n8rvdey6avckmeax8qvcrqd7.