diff --git a/.zuul.yaml b/.zuul.yaml
index 57e537c..84fb6da 100644
--- a/.zuul.yaml
+++ b/.zuul.yaml
@@ -19,8 +19,8 @@
     parent: opendev-build-docker-image
     description: Build OpenDev Docker images for gear
     requires:
-      - python-base-container-image
-      - python-builder-container-image
+      - python-base-3.9-bullseye-container-image
+      - python-builder-3.9-bullseye-container-image
     provides: gear-container-image
     vars: &gear_opendev_image_vars
       zuul_work_dir: src/opendev.org/opendev/gear
@@ -34,8 +34,8 @@
     parent: opendev-upload-docker-image
     description: Build OpenDev gear Docker images and upload to Docker Hub.
     requires:
-      - python-base-container-image
-      - python-builder-container-image
+      - python-base-3.9-bullseye-container-image
+      - python-builder-3.9-bullseye-container-image
     provides: gear-container-image
     vars: *gear_opendev_image_vars
     secrets:
diff --git a/Dockerfile b/Dockerfile
index 13a86af..3c75b9f 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -13,12 +13,12 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM opendevorg/python-builder as builder
+FROM opendevorg/python-builder:3.9-bullseye as builder
 
 COPY . /tmp/src
 RUN assemble
 
-FROM opendevorg/python-base as geard
+FROM opendevorg/python-base:3.9-bullseye as geard
 
 COPY --from=builder /output/ /output
 RUN /output/install-from-bindep