diff --git a/containers/base-ops/Dockerfile b/containers/base-ops/Dockerfile
index 1d3fcfb3..57af76b5 100644
--- a/containers/base-ops/Dockerfile
+++ b/containers/base-ops/Dockerfile
@@ -1,11 +1,13 @@
 ARG BASEIMAGE=rucio/rucio-server
 ARG BASETAG=release-1.30.0
- 
-FROM $BASEIMAGE:$BASETAG
+ARG BUILD_DATE
+
+FROM ${BASEIMAGE}:${BASETAG}
 LABEL maintainer="VRE Team @ CERN 22/23 - E. Garcia, E. Gazzarrini, D. Gosein"
 LABEL org.opencontainers.image.source https://github.com/vre-hub/vre
-ARG BUILD_DATE
-LABEL org.label-schema.build-date=$BUILD_DATE
+LABEL org.label-schema.build-date=${BUILD_DATE}
+
+USER root
 
 # cleanup yum cache
 RUN yum upgrade -y \
@@ -16,13 +18,11 @@ RUN yum upgrade -y \
 RUN yum -y install git htop wget voms-clients-cpp
 RUN pip install --upgrade pip
 
-USER root
-
 # EGI trust anchors
 RUN curl -Lo /etc/yum.repos.d/egi-trustanchors.repo https://repository.egi.eu/sw/production/cas/1/current/repo-files/egi-trustanchors.repo \
-    && yum update -y 
+    && yum update -y
 
-RUN yum -y install gfal2* python3-gfal2 xrootd-client voms-clients-java 
+RUN yum -y install gfal2* python3-gfal2 xrootd-client voms-clients-java
 RUN yum -y install ca-certificates ca-policy-egi-core
 
 # Install CERN CA certs from CERN maintained mirrors
@@ -32,13 +32,13 @@ RUN yum install -y CERN-CA-certs
 
 # ESCAPE VOMS setup
 RUN mkdir -p /etc/vomses \
-    && wget https://indigo-iam.github.io/escape-docs/voms-config/voms-escape.cloud.cnaf.infn.it.vomses -O /etc/vomses/voms-escape.cloud.cnaf.infn.it.vomses
-RUN mkdir -p /etc/grid-security/vomsdir/escape \
+    && wget https://indigo-iam.github.io/escape-docs/voms-config/voms-escape.cloud.cnaf.infn.it.vomses -O /etc/vomses/voms-escape.cloud.cnaf.infn.it.vomses \
+    && mkdir -p /etc/grid-security/vomsdir/escape \
     && wget https://indigo-iam.github.io/escape-docs/voms-config/voms-escape.cloud.cnaf.infn.it.lsc -O /etc/grid-security/vomsdir/escape/voms-escape.cloud.cnaf.infn.it.lsc
 
 # Install latest kubectl
-RUN curl -o /usr/bin/kubectl -L https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl
-RUN chmod +x /usr/bin/kubectl
+RUN curl -o /usr/bin/kubectl -L https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl \
+    && chmod +x /usr/bin/kubectl
 
 WORKDIR /home