diff --git a/docker/ntpd/Dockerfile b/docker/ntpd/Dockerfile
index b79c42d..6b50ff6 100644
--- a/docker/ntpd/Dockerfile
+++ b/docker/ntpd/Dockerfile
@@ -17,7 +17,7 @@
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
-FROM alpine:3.12
+FROM alpine:3.15
 
 RUN apk update && apk add chrony && \
     chown -R chrony:chrony /var/lib/chrony
diff --git a/requirements.txt b/requirements.txt
index 0de5e34..27023fb 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,4 @@
+pytz
 Django
 djangorestframework
 django-health-check