diff --git a/CMakeLists.txt b/CMakeLists.txt
index 134660a..7807ff1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,8 +31,8 @@ status_print(project_version)
 declare_cache_var(ZENOHCXX_ZENOHC ON BOOL "Build for Zenoh-c target")
 declare_cache_var(ZENOHCXX_ZENOHPICO OFF BOOL "Build for Zenoh-pico target")
 declare_cache_var(ZENOHCXX_EXAMPLES_PROTOBUF ON BOOL "Build Protobuf example (turn off if you have problems with installed Protobuf version)")
-declare_cache_var(ENABLE_TESTS "Enable building tests" ON)
-declare_cache_var(ENABLE_EXAMPLES "Enable building examples" ON)
+declare_cache_var(ENABLE_TESTS ON BOOL "Enable building tests" ON)
+declare_cache_var(ENABLE_EXAMPLES ON BOOL "Enable building examples" ON)
 
 set_default_build_type(Release)