diff --git a/library/library.pro b/library/library.pro
index 045b98f..2a3a5d7 100644
--- a/library/library.pro
+++ b/library/library.pro
@@ -8,6 +8,9 @@ INCLUDEPATH += $$_PRO_FILE_PWD_/include
 INCLUDEPATH += $$_PRO_FILE_PWD_/include/mobilisis
 INCLUDEPATH += $$_PRO_FILE_PWD_/include/rapidjson
 
+win32 {
+CONFIG+=-DCALCULATE_LIBRARY_EXPORTS
+}
 
 SOURCES += \
     src/calculator_functions.cpp \