diff --git a/CMakeLists.txt b/CMakeLists.txt
index be83334..156390f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,7 +3,6 @@ project(curtle VERSION 0.1.1 LANGUAGES C)
 
 include(GNUInstallDirs)
 include(CMakePackageConfigHelpers)
-include(CTest)
 
 set(CMAKE_C_STANDARD 11)
 set(CMAKE_C_STANDARD_REQUIRED ON)
@@ -54,7 +53,7 @@ install(FILES
         DESTINATION ${CMAKE_INSTALL_LIBDIR}/cmake/curtle
 )
 
-if(BUILD_TESTING)
+if(${PROJECT_IS_TOP_LEVEL})
     enable_testing()
     add_subdirectory(tests)
 endif()
\ No newline at end of file