diff --git a/CMakeLists.txt b/CMakeLists.txt
index b42e0aa34..b90de0661 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -158,6 +158,8 @@ file( COPY CalamaresAddBrandingSubdirectory.cmake DESTINATION "${PROJECT_BINARY_
 
 set( CALAMARES_LIBRARIES calamares )
 
+set( THIRDPARTY_DIR "${CMAKE_SOURCE_DIR}/thirdparty" )
+
 add_subdirectory( thirdparty )
 add_subdirectory( src )