If the recipe change is small you can create your own file that imports the existing package and extends it to modify the version.
This is a minimal example that inherits from the existing one
(define-module (mystuffypackages)
#:use-module (guix packages)
#:use-module (guix download)
#:use-module (gnu packages)
#:use-module (gnu packages education)
)
(define-public my-anki
(package
(inherit anki)
(version "2.1.65")
(source
(origin
(method url-fetch)
;; Changed the url to github - could not download from site archive
(uri (string-append "https://github.com/ankitects/anki/archive/refs/tags/"
version ".tar.gz"))
(sha256
(base32 "1s28kdaw864rj6x9zgq5wwwl0gi5cyn2kg91jkq05v1bwgl3f76a"))
;; FIXME 2.1.16 uses a patch - check education.scm - it is not
;; applying
))
;; FIXME currently failing to build due to disable-update-check
))
my-anki
You can call guix build directly to build the package from this file. To be clear this is currently failing for me :D
Check this blog article for a pretty nice overview of how to create your own packages and channel https://guix.gnu.org/blog/2023/from-development-environments-to-continuous-integrationthe-ultimate-guide-to-software-development-with-guix/