diff --git a/build/scripts/migration/script.d/02-migrate-user-service.sh b/build/scripts/migration/script.d/02-migrate-user-service.sh
index 3e95f2a..9e35a0e 100644
--- a/build/scripts/migration/script.d/02-migrate-user-service.sh
+++ b/build/scripts/migration/script.d/02-migrate-user-service.sh
@@ -58,29 +58,37 @@ __is_migration_needed() {
 }
 
 BUILD_PATH=$(dirname "${BASH_SOURCE[0]}")/../../..
-SOURCE_ROOT=${BUILD_PATH}/sysroot
 
-APP_NAME="casaos-user-service"
-APP_NAME_FORMAL="CasaOS-UserService"
-APP_NAME_SHORT="user-service"
-APP_NAME_LEGACY="casaos"
+readonly BUILD_PATH
+readonly SOURCE_ROOT=${BUILD_PATH}/sysroot
+
+readonly APP_NAME="casaos-user-service"
+readonly APP_NAME_FORMAL="CasaOS-UserService"
+readonly APP_NAME_SHORT="user-service"
+readonly APP_NAME_LEGACY="casaos"
 
 # check if migration is needed
-SOURCE_BIN_PATH=${SOURCE_ROOT}/usr/bin
-SOURCE_BIN_FILE=${SOURCE_BIN_PATH}/${APP_NAME}
+readonly SOURCE_BIN_PATH=${SOURCE_ROOT}/usr/bin
+readonly SOURCE_BIN_FILE=${SOURCE_BIN_PATH}/${APP_NAME}
+
+readonly CURRENT_BIN_PATH=/usr/bin
+readonly CURRENT_BIN_PATH_LEGACY=/usr/local/bin
+readonly CURRENT_BIN_FILE=${CURRENT_BIN_PATH}/${APP_NAME}
 
-CURRENT_BIN_PATH=/usr/bin
-CURRENT_BIN_PATH_LEGACY=/usr/local/bin
-CURRENT_BIN_FILE=${CURRENT_BIN_PATH}/${APP_NAME}
 CURRENT_BIN_FILE_LEGACY=$(realpath -e ${CURRENT_BIN_PATH}/${APP_NAME_LEGACY} || realpath -e ${CURRENT_BIN_PATH_LEGACY}/${APP_NAME_LEGACY} || which ${APP_NAME_LEGACY} || echo CURRENT_BIN_FILE_LEGACY_NOT_FOUND)
+readonly CURRENT_BIN_FILE_LEGACY
 
 SOURCE_VERSION="$(${SOURCE_BIN_FILE} -v)"
+readonly SOURCE_VERSION
+
 CURRENT_VERSION="$(${CURRENT_BIN_FILE} -v || ${CURRENT_BIN_FILE_LEGACY} -v || (stat "${CURRENT_BIN_FILE_LEGACY}" > /dev/null && echo LEGACY_WITHOUT_VERSION) || echo CURRENT_VERSION_NOT_FOUND)"
+readonly CURRENT_VERSION
 
 __info_done "CURRENT_VERSION: ${CURRENT_VERSION}"
 __info_done "SOURCE_VERSION: ${SOURCE_VERSION}"
 
 NEED_MIGRATION=$(__is_migration_needed "${CURRENT_VERSION}" "${SOURCE_VERSION}" && echo "true" || echo "false")
+readonly NEED_MIGRATION
 
 if [ "${NEED_MIGRATION}" = "false" ]; then
     __info_done "Migration is not needed."
@@ -93,9 +101,9 @@ if [ -z "${MIGRATION_SERVICE_DIR}" ]; then
     MIGRATION_SERVICE_DIR=${BUILD_PATH}/scripts/migration/service.d/${APP_NAME_SHORT}
 fi
 
-MIGRATION_LIST_FILE=${MIGRATION_SERVICE_DIR}/migration.list
-MIGRATION_PATH=()
+readonly MIGRATION_LIST_FILE=${MIGRATION_SERVICE_DIR}/migration.list
 
+MIGRATION_PATH=()
 CURRENT_VERSION_FOUND="false"
 
 # a VERSION_PAIR looks like "v0.3.5 v0.3.6-alpha2"
diff --git a/build/scripts/setup/script.d/02-setup-user-service.sh b/build/scripts/setup/script.d/02-setup-user-service.sh
index 3553c72..93a3474 100755
--- a/build/scripts/setup/script.d/02-setup-user-service.sh
+++ b/build/scripts/setup/script.d/02-setup-user-service.sh
@@ -4,7 +4,8 @@ set -e
 
 BUILD_PATH=$(dirname "${BASH_SOURCE[0]}")/../../..
 
-APP_NAME_SHORT=user-service
+readonly BUILD_PATH
+readonly APP_NAME_SHORT=user-service
 
 __get_setup_script_directory_by_os_release() {
 	pushd "$(dirname "${BASH_SOURCE[0]}")/../service.d/${APP_NAME_SHORT}" >/dev/null
@@ -39,9 +40,10 @@ __get_setup_script_directory_by_os_release() {
 }
 
 SETUP_SCRIPT_DIRECTORY=$(__get_setup_script_directory_by_os_release)
-SETUP_SCRIPT_FILENAME="setup-${APP_NAME_SHORT}.sh"
 
-SETUP_SCRIPT_FILEPATH="${SETUP_SCRIPT_DIRECTORY}/${SETUP_SCRIPT_FILENAME}"
+readonly SETUP_SCRIPT_DIRECTORY
+readonly SETUP_SCRIPT_FILENAME="setup-${APP_NAME_SHORT}.sh"
+readonly SETUP_SCRIPT_FILEPATH="${SETUP_SCRIPT_DIRECTORY}/${SETUP_SCRIPT_FILENAME}"
 
 {
     echo "🟩 Running ${SETUP_SCRIPT_FILENAME}..."
diff --git a/build/scripts/setup/service.d/user-service/debian/setup-user-service.sh b/build/scripts/setup/service.d/user-service/debian/setup-user-service.sh
index 0e5494f..98d262b 100644
--- a/build/scripts/setup/service.d/user-service/debian/setup-user-service.sh
+++ b/build/scripts/setup/service.d/user-service/debian/setup-user-service.sh
@@ -2,13 +2,13 @@
 
 set -e
 
-APP_NAME="casaos-user-service"
-APP_NAME_SHORT="user-service"
+readonly APP_NAME="casaos-user-service"
+readonly APP_NAME_SHORT="user-service"
 
 # copy config files
-CONF_PATH=/etc/casaos
-CONF_FILE=${CONF_PATH}/${APP_NAME_SHORT}.conf
-CONF_FILE_SAMPLE=${CONF_PATH}/${APP_NAME_SHORT}.conf.sample
+readonly CONF_PATH=/etc/casaos
+readonly CONF_FILE=${CONF_PATH}/${APP_NAME_SHORT}.conf
+readonly CONF_FILE_SAMPLE=${CONF_PATH}/${APP_NAME_SHORT}.conf.sample
 
 if [ ! -f "${CONF_FILE}" ]; then \
     echo "Initializing config file..."