(use-modules (guix packages)
             (guix download)
             (gnu packages web))

(define custom-ikiwiki
  (let ((commit "git-annex-album-2-rebased"))
    (package
      (inherit ikiwiki)
      (source (origin
                (method url-fetch)
                (uri (string-append
                      "https://git.cbaines.net/ikiwiki/snapshot/ikiwiki-"
                      commit
                      ".tar.gz"))
                (sha256
                 (base32
                  "1l6xmndl5wdhavcxc8fcw45g5d4ah9a7yp36qrapns80p2g5r0c7"))
                (file-name (string-append "ikiwiki-" (string-take commit 7))))))))

custom-ikiwiki