diff --git a/Makefile.am b/Makefile.am
index 26cc8db..35418ec 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,5 +1,12 @@
 ACLOCAL_AMFLAGS = -I m4
 
+# Ignore system headers
+CODE_COVERAGE_IGNORE_PATTERN = '/include/*' '/usr/include/*' '$(includedir)/*'
+# Ignore the real implementation sources for sd_event
+CODE_COVERAGE_IGNORE_PATTERN += \
+    '$(abs_builddir)/src/sdeventplus/internal/sdevent.*'
+export CODE_COVERAGE_IGNORE_PATTERN
+
 export AM_CPPFLAGS = -I$(abs_builddir)/src -I$(abs_srcdir)/src \
                      $(SYSTEMD_CFLAGS) $(CODE_COVERAGE_CPPFLAGS)
 export AM_CFLAGS = $(CODE_COVERAGE_CFLAGS)