diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5136220..c41bdcf 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -316,6 +316,13 @@ if(BUILD_RESOURCES)
   endif()
 endif()
 
+# check if AlarmController.h needs FileSystem member
+file(STRINGS "${InfiniTime_DIR}/src/components/alarm/AlarmController.h" alarmControllerFileSystemEntries REGEX "Controllers::FS")
+if(NOT alarmControllerFileSystemEntries STREQUAL "")
+  message(STATUS "detected AlarmController.h using 'Controllers::FS'")
+  set_source_files_properties(main.cpp PROPERTIES COMPILE_DEFINITIONS ALARMCONTROLLER_NEEDS_FS)
+endif()
+
 list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 # Special case for SDL2 dependency, goal is to find a config that exports SDL2::SDL2 target
 # libsdl2-dev has a `sdl2-config.cmake` that doesn't export this, but vcpkg does..
diff --git a/main.cpp b/main.cpp
index 1f22066..f410c73 100644
--- a/main.cpp
+++ b/main.cpp
@@ -354,7 +354,11 @@ Pinetime::Controllers::MotionController motionController;
 Pinetime::Controllers::TimerController timerController;
 #endif
 
+#if defined(ALARMCONTROLLER_NEEDS_FS)
+Pinetime::Controllers::AlarmController alarmController {dateTimeController, fs};
+#else
 Pinetime::Controllers::AlarmController alarmController {dateTimeController};
+#endif
 Pinetime::Controllers::TouchHandler touchHandler;
 Pinetime::Controllers::ButtonHandler buttonHandler;
 Pinetime::Controllers::BrightnessController brightnessController {};