diff --git a/guix-data-service/model/git-repository.scm b/guix-data-service/model/git-repository.scm
index f6cceb1..8fcbb43 100644
--- a/guix-data-service/model/git-repository.scm
+++ b/guix-data-service/model/git-repository.scm
@@ -226,7 +226,9 @@ FROM git_repositories WHERE id = $1"
      (string->number id))))
 
 (define* (git-repository-url->git-repository-id conn url
-                                                #:key (authenticate? #t))
+                                                #:key
+                                                (create-if-missing? #t)
+                                                (authenticate? #t))
   (define (->boolean value)
     (if value "TRUE" "FALSE"))
 
@@ -245,14 +247,15 @@ SET fetch_with_authentication = "
                                    " WHERE id = " id ";"))
         id)
        (()
-        (caar
-         (exec-query conn
-                     (string-append
-                      "INSERT INTO git_repositories "
-                      "(url, fetch_with_authentication) "
-                      "VALUES "
-                      "('" url "', " (->boolean authenticate?) ") "
-                      "RETURNING id"))))))))
+        (and create-if-missing?
+             (caar
+              (exec-query conn
+                          (string-append
+                           "INSERT INTO git_repositories "
+                           "(url, fetch_with_authentication) "
+                           "VALUES "
+                           "('" url "', " (->boolean authenticate?) ") "
+                           "RETURNING id")))))))))
 
 (define (guix-revisions-and-jobs-for-git-repository conn git-repository-id)
   (define query