diff --git a/scripts/prepare_release.sh b/scripts/prepare_release.sh
index 955d22d51..c506cfe30 100755
--- a/scripts/prepare_release.sh
+++ b/scripts/prepare_release.sh
@@ -15,8 +15,8 @@ VERSION=$1
 SKIP_TESTS=false
 
 # Check for the --skip_tests flag
-if [ "$2" == "--skip_tests" ]; then
-  SKIP_TESTS=true
+if [ "${2-}" == "--skip_tests" ]; then
+  SKIP_TESTS="true"
 fi
 
 # fail if not clean working directory
diff --git a/scripts/release.sh b/scripts/release.sh
index 9c1183772..7d8666b31 100755
--- a/scripts/release.sh
+++ b/scripts/release.sh
@@ -13,8 +13,8 @@ fi
 SKIP_TESTS=false
 
 # Check for the --skip_tests flag
-if [ "$1" == "--skip_tests" ]; then
-  SKIP_TESTS=true
+if [ "${1-}" == "--skip_tests" ]; then
+  SKIP_TESTS="true"
 fi
 
 APPS=(api sync-worker)