diff --git a/make/defs.mk b/make/defs.mk
index 8605491e..46647ac1 100644
--- a/make/defs.mk
+++ b/make/defs.mk
@@ -381,7 +381,7 @@ INSTALLED_CGI               += $(addprefix $(INSTALL_CGIDIR)/,$(EXE_CGI))
 # -- SYSTEMD
 INSTALLATION_FILE_TYPES     += SYSTEMD
 BUILD_SYSTEMDDIR             = $(TOPDIR)/bin/systemd
-LOCAL_SYSTEMD               += $(filter-out $(DONT_INSTALL),$(wildcard *.service *.mount *.target *.timer *.socket))
+LOCAL_SYSTEMD               += $(filter-out $(DONT_INSTALL),$(wildcard *.service *.mount *.target *.timer *.socket *.slice))
 INSTALL_SYSTEMDDIR           = $(SYSTEMD_DIR)
 INSTALLED_SYSTEMD           += $(addprefix $(INSTALL_SYSTEMDDIR)/,$(LOCAL_SYSTEMD))