diff --git a/templates/gitlab-ci-maven.yml b/templates/gitlab-ci-maven.yml
index 1f52146ab7407fd25b6abb62c8e4f57be528ead8..d4166223ac267accef34a68d18c1ccd18ffc5450 100644
--- a/templates/gitlab-ci-maven.yml
+++ b/templates/gitlab-ci-maven.yml
@@ -491,7 +491,7 @@ stages:
     else
       log_info "Publish version \\e[33;1m${pom_version}\\e[0m..."
       # shellcheck disable=SC2086
-      mvn ${TRACE+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args $MAVEN_DEPLOY_ARGS
+      mvn ${TRACE:+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args $MAVEN_DEPLOY_ARGS
     fi
   }
 
@@ -542,7 +542,7 @@ mvn-build:
   stage: build
   script:
     - maybe_inject_slug_in_version
-    - mvn ${TRACE+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args $MAVEN_BUILD_ARGS
+    - mvn ${TRACE:+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args $MAVEN_BUILD_ARGS
     - output_coverage
   # code coverage RegEx
   coverage: '/^(\d+\.?\d*\%) covered$/'
@@ -586,10 +586,10 @@ mvn-sonar:
         export SONAR_TOKEN="$SONAR_AUTH_TOKEN"
       fi
     - >-
-      mvn ${TRACE+-Dsonar.verbose=true} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args
-      ${SONAR_LOGIN+-Dsonar.login=$SONAR_LOGIN}
-      ${SONAR_PASSWORD+-Dsonar.password=$SONAR_PASSWORD}
-      ${SONAR_QUALITY_GATE_ENABLED+-Dsonar.qualitygate.wait=$SONAR_QUALITY_GATE_ENABLED}
+      mvn ${TRACE:+-Dsonar.verbose=true} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args
+      ${SONAR_LOGIN:+-Dsonar.login=$SONAR_LOGIN}
+      ${SONAR_PASSWORD:+-Dsonar.password=$SONAR_PASSWORD}
+      ${SONAR_QUALITY_GATE_ENABLED:+-Dsonar.qualitygate.wait=$SONAR_QUALITY_GATE_ENABLED}
       $SONAR_BASE_ARGS
   rules:
     # exclude if $SONAR_URL and $SONAR_HOST_URL not set
@@ -603,7 +603,7 @@ mvn-dependency-check:
   # force no dependency
   dependencies: []
   script:
-    - mvn ${TRACE+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args $MAVEN_DEPENDENCY_CHECK_ARGS
+    - mvn ${TRACE:+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args $MAVEN_DEPENDENCY_CHECK_ARGS
   artifacts:
     name: "$CI_JOB_NAME artifacts from $CI_PROJECT_NAME on $CI_COMMIT_REF_SLUG"
     expire_in: 1 day
@@ -627,7 +627,7 @@ mvn-no-snapshot-deps:
   stage: test
   needs: []
   script:
-    - mvn ${TRACE+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args enforcer:enforce -Drules=requireReleaseDeps
+    - mvn ${TRACE:+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args enforcer:enforce -Drules=requireReleaseDeps
   rules:
     # exclude if disabled
     - if: '$MVN_FORBID_SNAPSHOT_DEPENDENCIES_DISABLED == "true"'
@@ -706,12 +706,12 @@ mvn-release:
         fi
       fi
     - >-
-      mvn ${TRACE+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args
+      mvn ${TRACE:+-X} $MAVEN_CLI_OPTS $mvn_settings_opt $java_proxy_args
       ${scm_auth_args} ${semrel_args}
-      ${MAVEN_RELEASE_VERSION+-DreleaseVersion="$MAVEN_RELEASE_VERSION"}
-      ${MAVEN_RELEASE_SCM_COMMENT_PREFIX+-DscmCommentPrefix="$MAVEN_RELEASE_SCM_COMMENT_PREFIX"}
-      ${MAVEN_RELEASE_SCM_RELEASE_COMMENT+-DscmReleaseCommitComment="$MAVEN_RELEASE_SCM_RELEASE_COMMENT"}
-      ${MAVEN_RELEASE_SCM_DEV_COMMENT+-DscmDevelopmentCommitComment="$MAVEN_RELEASE_SCM_DEV_COMMENT"}
+      ${MAVEN_RELEASE_VERSION:+-DreleaseVersion="$MAVEN_RELEASE_VERSION"}
+      ${MAVEN_RELEASE_SCM_COMMENT_PREFIX:+-DscmCommentPrefix="$MAVEN_RELEASE_SCM_COMMENT_PREFIX"}
+      ${MAVEN_RELEASE_SCM_RELEASE_COMMENT:+-DscmReleaseCommitComment="$MAVEN_RELEASE_SCM_RELEASE_COMMENT"}
+      ${MAVEN_RELEASE_SCM_DEV_COMMENT:+-DscmDevelopmentCommitComment="$MAVEN_RELEASE_SCM_DEV_COMMENT"}
       ${MAVEN_RELEASE_ARGS}
   rules:
     # exclude if $MAVEN_DEPLOY_ENABLED not set