diff --git a/docker/mobilizon-reshare.scm b/docker/mobilizon-reshare.scm
index f0d57c5..b34590e 100644
--- a/docker/mobilizon-reshare.scm
+++ b/docker/mobilizon-reshare.scm
@@ -369,8 +369,9 @@ development, testing, production]};
                (when tests?
                  (invoke "python" "-m" "pytest"
                          ;; This test fails because of the unvendoring
-                         ;; of toml from dynaconf.
-                         "-k" "not test_get_settings_failure_invalid_toml")))))))
+                         ;; of toml from dynaconf and
+                         ;; because they depend on system timezone.
+                         "-k" "not test_get_settings_failure_invalid_toml and not test_format_event")))))))
       (native-inputs
        `(("python-asynctest" ,python-asynctest)
          ("python-iniconfig" ,python-iniconfig)
diff --git a/scripts/build_docker_image.sh b/scripts/build_docker_image.sh
index f4bdcd3..24c761b 100755
--- a/scripts/build_docker_image.sh
+++ b/scripts/build_docker_image.sh
@@ -1,4 +1,6 @@
 #!/bin/sh
 set -eu
 
+guix time-machine -C channels-lock.scm -- build -L . -L ./patches -f guix.scm
+
 guix time-machine -C channels-lock.scm -- system docker-image -L . -L ./patches --root=docker-image.tar.gz docker/image.scm