diff --git a/weekly.sh b/weekly.sh
index 155a7d5..e240a8b 100755
--- a/weekly.sh
+++ b/weekly.sh
@@ -3,20 +3,20 @@
 set -e
 set -x
 
-JENKINS_VERSION=`curl -sq https://api.github.com/repos/jenkinsci/jenkins/tags | grep '"name":' | grep -o '[0-9]\.[0-9]*'  | uniq | sort --version-sort | tail -1`
-echo $JENKINS_VERSION
+JENKINS_VERSION=$(curl -sq https://api.github.com/repos/jenkinsci/jenkins/tags | grep '"name":' | grep -o '[0-9]\.[0-9]*'  | uniq | sort --version-sort | tail -1)
+echo "$JENKINS_VERSION"
 
-JENKINS_SHA=`curl http://repo.jenkins-ci.org/simple/releases/org/jenkins-ci/main/jenkins-war/${JENKINS_VERSION}/jenkins-war-${JENKINS_VERSION}.war.sha1`
-echo $JENKINS_SHA
+JENKINS_SHA=$(curl "http://repo.jenkins-ci.org/simple/releases/org/jenkins-ci/main/jenkins-war/${JENKINS_VERSION}/jenkins-war-${JENKINS_VERSION}.war.sha1")
+echo "$JENKINS_SHA"
 
-docker build --build-arg JENKINS_VERSION=$JENKINS_VERSION \
-             --build-arg JENKINS_SHA=$JENKINS_SHA \
+docker build --build-arg "JENKINS_VERSION=$JENKINS_VERSION" \
+             --build-arg "JENKINS_SHA=$JENKINS_SHA" \
              --no-cache --pull \
-             --tag jenkinsci/jenkins:$JENKINS_VERSION .
+             --tag "jenkinsci/jenkins:$JENKINS_VERSION" .
 
-docker tag -f jenkinsci/jenkins:$JENKINS_VERSION jenkinsci/jenkins:latest
+docker tag -f "jenkinsci/jenkins:$JENKINS_VERSION" jenkinsci/jenkins:latest
 
-docker push jenkinsci/jenkins:$JENKINS_VERSION
+docker push "jenkinsci/jenkins:$JENKINS_VERSION"
 docker push jenkinsci/jenkins:latest