diff --git a/lib/io/Makefile.inc b/lib/io/Makefile.inc
index 8bd7ee23e..f313b6667 100644
--- a/lib/io/Makefile.inc
+++ b/lib/io/Makefile.inc
@@ -33,9 +33,9 @@ endif
 endif
 
 %.pb-c.c %.pb-c.h: %.proto
-	protoc-c --proto_path=$(SRCDIR) --c_out=$(SRCDIR) $(realpath $^)
-
-$(BUILDDIR)/%.pb-c.o: LIB_CFLAGS += -I$(SRCDIR) 
+	protoc-c --proto_path=$(SRCDIR) --c_out=$(SRCDIR) --dependency_out=$(BUILDDIR)/$*.d $(realpath $^)
 
+$(BUILDDIR)/%.pb-c.o: LIB_CFLAGS += -I$(SRCDIR)
+$(BUILDDIR)/lib/io/protobuf.o:  LIB_CFLAGS += -I$(SRCDIR)/lib/io
+	
 $(BUILDDIR)/lib/io/protobuf.o: lib/io/villas.pb-c.h
-
diff --git a/lib/io/villas.proto b/lib/io/villas.proto
index fe1ba9cf8..16d1ad85c 100644
--- a/lib/io/villas.proto
+++ b/lib/io/villas.proto
@@ -21,6 +21,8 @@
 /// along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ////////////////////////////////////////////////////////////////////////////////////
 
+syntax = "proto2";
+
 package villas.node;
 
 message Message {