diff --git a/dockerfiles/swh-objstorage/Dockerfile b/dockerfiles/swh-objstorage/Dockerfile
index de52690..8f84487 100644
--- a/dockerfiles/swh-objstorage/Dockerfile
+++ b/dockerfiles/swh-objstorage/Dockerfile
@@ -1,16 +1,16 @@
 FROM python:3
 
-export DEBIAN_FRONTEND=noninteractive && \
+RUN export DEBIAN_FRONTEND=noninteractive && \
   apt-get update && \
   apt-get install -y \
     libsystemd-dev
 
 RUN pip install swh-objstorage
 COPY objstorage.yml /
 COPY entrypoint.sh /
 
 RUN mkdir -p /srv/softwareheritage/objects
 
 ENTRYPOINT ["/entrypoint.sh"]
 
 EXPOSE 5003
diff --git a/dockerfiles/swh-storage/Dockerfile b/dockerfiles/swh-storage/Dockerfile
index 5838a14..f06f94b 100644
--- a/dockerfiles/swh-storage/Dockerfile
+++ b/dockerfiles/swh-storage/Dockerfile
@@ -1,14 +1,14 @@
 FROM python:3
 
-export DEBIAN_FRONTEND=noninteractive && \
+RUN export DEBIAN_FRONTEND=noninteractive && \
   apt-get update && \
   apt-get install -y \
     libsystemd-dev postgresql-client
 
 RUN pip install swh-storage
 COPY storage.yml /
 COPY entrypoint.sh /
 
 ENTRYPOINT ["/entrypoint.sh"]
 
 EXPOSE 5002