diff --git a/Makefile.am b/Makefile.am
index 48b9268..f9a608d 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -27,7 +27,7 @@
 libmapper_LTLIBRARIES = libmapper.la
 libmapper_la_SOURCES = libmapper/mapper.c
 libmapper_la_LDFLAGS = $(SYSTEMD_LIBS) -version-info 1:0:0 -shared
-libmapper_la_CFLAGS = $(SYSTEMD_CFLAGS)
+libmapper_la_CFLAGS = $(SYSTEMD_CFLAGS) -fvisibility=hidden
 
 mapperx_SOURCES = src/main.cpp src/argument.cpp src/processing.cpp \
 	src/associations.cpp