diff --git a/Makefile.am b/Makefile.am
index 50f4683..caa13dc 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -11,7 +11,7 @@
 libmapper_la_LDFLAGS = $(SYSTEMD_LIBS) -version-info 1:0:0 -shared
 libmapper_la_CFLAGS = $(SYSTEMD_CFLAGS)
 
-mapperx_SOURCES = src/main.cpp
+mapperx_SOURCES = src/main.cpp src/argument.cpp
 mapperx_LDFLAGS = $(SDBUSPLUS_LIBS) -pthread -ltinyxml2
 mapperx_CXXFLAGS = $(SYSTEMD_CFLAGS) -DBOOST_SYSTEM_NO_DEPRECATED -DBOOST_ERROR_CODE_HEADER_ONLY -DBOOST_ALL_NO_LIB