diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 797e76139..87447270b 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -708,15 +708,11 @@ else()
 endif()
 
 add_custom_command( OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/xlat_parser.c ${CMAKE_CURRENT_BINARY_DIR}/xlat_parser.h
-	COMMAND ${CMAKE_COMMAND} -E copy_if_different ${CMAKE_CURRENT_SOURCE_DIR}/xlat/xlat_parser.y .
-	COMMAND lemon xlat_parser.y
-	WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+	COMMAND lemon -C${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/xlat/xlat_parser.y
 	DEPENDS lemon ${CMAKE_CURRENT_SOURCE_DIR}/xlat/xlat_parser.y )
 
 add_custom_command( OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/zcc-parse.c ${CMAKE_CURRENT_BINARY_DIR}/zcc-parse.h
-	COMMAND ${CMAKE_COMMAND} -E copy_if_different ${CMAKE_CURRENT_SOURCE_DIR}/zscript/zcc-parse.lemon .
-	COMMAND lemon zcc-parse.lemon
-	WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}
+	COMMAND lemon -C${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/zscript/zcc-parse.lemon
 	DEPENDS lemon ${CMAKE_CURRENT_SOURCE_DIR}/zscript/zcc-parse.lemon )
 
 add_custom_command( OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/sc_man_scanner.h