diff --git a/debian/bookworm-slim/hotspot/Dockerfile b/debian/bookworm-slim/hotspot/Dockerfile
index 234aad51ce..50793b6bd2 100644
--- a/debian/bookworm-slim/hotspot/Dockerfile
+++ b/debian/bookworm-slim/hotspot/Dockerfile
@@ -134,17 +134,17 @@ ENV JENKINS_HOME=$JENKINS_HOME \
 # If you bind mount a volume from the host or a data container, #
 # ensure you use the same uid(e.g. 1000)                        #
 #---------------------------------------------------------------#
-RUN mkdir -p $JENKINS_HOME \
-    && chown ${uid}:${gid} $JENKINS_HOME \
-    && groupadd -g ${gid} ${group} \
-    && useradd -d "$JENKINS_HOME" -u ${uid} -g ${gid} -l -m -s /bin/bash ${user}
+RUN mkdir -p "$JENKINS_HOME" \
+    && chown "${uid}":"${gid}" "$JENKINS_HOME" \
+    && groupadd -g "${gid}" "${group}" \
+    && useradd -d "$JENKINS_HOME" -u "${uid}" -g "${gid}" -l -m -s /bin/bash ${user}
 
 #-----------------------------------------------------------------------------------#
 # $REF (defaults to `/usr/share/jenkins/ref/`) contains all reference configuration #
 # we want to set on a fresh new installation. Use it to bundle additional plugins   #
 # or config file with your custom jenkins Docker image.                             #
 #-----------------------------------------------------------------------------------#
-RUN mkdir -p ${REF}/init.groovy.d
+RUN mkdir -p "${REF}"/init.groovy.d
 
 #------------------------------------------------------------------------#
 # JENKINS_SHA: jenkins.war checksum, download will be validated using it #
@@ -158,7 +158,7 @@ ARG JENKINS_SHA=910ea36cef37c45087e39d65e335988e036fccea47c79cc5a52e721a10cb1b49
 # could use ADD but this one does not check Last-Modified header neither does it allow to control checksum #
 # see https://github.com/docker/docker/issues/8331                                                         #
 #----------------------------------------------------------------------------------------------------------#
-RUN curl -fsSL ${JENKINS_URL} -o /usr/share/jenkins/jenkins.war \
+RUN curl -fsSL "${JENKINS_URL}" -o /usr/share/jenkins/jenkins.war \
     && echo "${JENKINS_SHA}  /usr/share/jenkins/jenkins.war" >/tmp/jenkins_sha \
     && sha256sum -c --strict /tmp/jenkins_sha \
     && rm -f /tmp/jenkins_sha
@@ -166,12 +166,12 @@ RUN curl -fsSL ${JENKINS_URL} -o /usr/share/jenkins/jenkins.war \
 ENV JENKINS_UC=https://updates.jenkins.io \
     JENKINS_UC_EXPERIMENTAL=https://updates.jenkins.io/experimental \
     JENKINS_INCREMENTALS_REPO_MIRROR=https://repo.jenkins-ci.org/incrementals
-RUN chown -R ${user} "$JENKINS_HOME" "$REF"
+RUN chown -R "${user}" "$JENKINS_HOME" "$REF"
 
 ARG PLUGIN_CLI_VERSION=2.13.2 \
     PLUGIN_CLI_URL=https://github.com/jenkinsci/plugin-installation-manager-tool/releases/download/${PLUGIN_CLI_VERSION}/jenkins-plugin-manager-${PLUGIN_CLI_VERSION}.jar
-RUN curl -fsSL ${PLUGIN_CLI_URL} -o /opt/jenkins-plugin-manager.jar \
-    && echo "$(curl -fsSL "${PLUGIN_CLI_URL}.sha256")  /opt/jenkins-plugin-manager.jar" >/tmp/jenkins_sha \
+RUN curl -fsSL "${PLUGIN_CLI_URL}" -o /opt/jenkins-plugin-manager.jar \
+    && echo "$(curl -fsSL ${PLUGIN_CLI_URL}.sha256)  /opt/jenkins-plugin-manager.jar" >/tmp/jenkins_sha \
     && sha256sum -c --strict /tmp/jenkins_sha \
     && rm -f /tmp/jenkins_sha
 
diff --git a/debian/bookworm/hotspot/Dockerfile b/debian/bookworm/hotspot/Dockerfile
index ce444eda91..2b0d3a1eb1 100644
--- a/debian/bookworm/hotspot/Dockerfile
+++ b/debian/bookworm/hotspot/Dockerfile
@@ -134,17 +134,17 @@ ENV JENKINS_HOME=$JENKINS_HOME \
 # If you bind mount a volume from the host or a data container, #
 # ensure you use the same uid(e.g. 1000)                        #
 #---------------------------------------------------------------#
-RUN mkdir -p $JENKINS_HOME \
-    && chown ${uid}:${gid} $JENKINS_HOME \
-    && groupadd -g ${gid} ${group} \
-    && useradd -d "$JENKINS_HOME" -u ${uid} -g ${gid} -l -m -s /bin/bash ${user}
+RUN mkdir -p "$JENKINS_HOME" \
+    && chown "${uid}":"${gid}" "$JENKINS_HOME" \
+    && groupadd -g "${gid}" "${group}" \
+    && useradd -d "$JENKINS_HOME" -u "${uid}" -g "${gid}" -l -m -s /bin/bash ${user}
 
 #-----------------------------------------------------------------------------------#
 # $REF (defaults to `/usr/share/jenkins/ref/`) contains all reference configuration #
 # we want to set on a fresh new installation. Use it to bundle additional plugins   #
 # or config file with your custom jenkins Docker image.                             #
 #-----------------------------------------------------------------------------------#
-RUN mkdir -p ${REF}/init.groovy.d
+RUN mkdir -p "${REF}"/init.groovy.d
 
 #------------------------------------------------------------------------#
 # JENKINS_SHA: jenkins.war checksum, download will be validated using it #
@@ -158,7 +158,7 @@ ARG JENKINS_SHA=910ea36cef37c45087e39d65e335988e036fccea47c79cc5a52e721a10cb1b49
 # could use ADD but this one does not check Last-Modified header neither does it allow to control checksum #
 # see https://github.com/docker/docker/issues/8331                                                         #
 #----------------------------------------------------------------------------------------------------------#
-RUN curl -fsSL ${JENKINS_URL} -o /usr/share/jenkins/jenkins.war \
+RUN curl -fsSL "${JENKINS_URL}" -o /usr/share/jenkins/jenkins.war \
     && echo "${JENKINS_SHA}  /usr/share/jenkins/jenkins.war" >/tmp/jenkins_sha \
     && sha256sum -c --strict /tmp/jenkins_sha \
     && rm -f /tmp/jenkins_sha
@@ -166,12 +166,12 @@ RUN curl -fsSL ${JENKINS_URL} -o /usr/share/jenkins/jenkins.war \
 ENV JENKINS_UC=https://updates.jenkins.io \
     JENKINS_UC_EXPERIMENTAL=https://updates.jenkins.io/experimental \
     JENKINS_INCREMENTALS_REPO_MIRROR=https://repo.jenkins-ci.org/incrementals
-RUN chown -R ${user} "$JENKINS_HOME" "$REF"
+RUN chown -R "${user}" "$JENKINS_HOME" "$REF"
 
 ARG PLUGIN_CLI_VERSION=2.13.2 \
     PLUGIN_CLI_URL=https://github.com/jenkinsci/plugin-installation-manager-tool/releases/download/${PLUGIN_CLI_VERSION}/jenkins-plugin-manager-${PLUGIN_CLI_VERSION}.jar
-RUN curl -fsSL ${PLUGIN_CLI_URL} -o /opt/jenkins-plugin-manager.jar \
-    && echo "$(curl -fsSL "${PLUGIN_CLI_URL}.sha256")  /opt/jenkins-plugin-manager.jar" >/tmp/jenkins_sha \
+RUN curl -fsSL "${PLUGIN_CLI_URL}" -o /opt/jenkins-plugin-manager.jar \
+    && echo "$(curl -fsSL ${PLUGIN_CLI_URL}.sha256)  /opt/jenkins-plugin-manager.jar" >/tmp/jenkins_sha \
     && sha256sum -c --strict /tmp/jenkins_sha \
     && rm -f /tmp/jenkins_sha