diff --git a/Makefile.am b/Makefile.am
index 42cc4d8..9c341d8 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -9,6 +9,7 @@
 		ethernet_interface.hpp
 
 phosphor_network_manager_SOURCES = \
+		ethernet_interface.cpp \
 		network_manager_main.cpp
 
 phosphor_network_manager_LDFLAGS = \