diff --git a/CommonLibs/config_defs.h b/CommonLibs/config_defs.h
new file mode 100644
index 0000000..8626166
--- /dev/null
+++ b/CommonLibs/config_defs.h
@@ -0,0 +1,20 @@
+#pragma once
+
+/*
+ * This file contains structures used by both VTY (C, dir CommonLibs) and
+ * osmo-trx (CXX, dir Transceiver52)
+ */
+
+enum FillerType {
+  FILLER_DUMMY,
+  FILLER_ZERO,
+  FILLER_NORM_RAND,
+  FILLER_EDGE_RAND,
+  FILLER_ACCESS_RAND,
+};
+
+enum ReferenceType {
+  REF_INTERNAL,
+  REF_EXTERNAL,
+  REF_GPS,
+};