diff --git a/include/with99/defres.h b/include/with99/defres.h
new file mode 100644
index 0000000..f7278b9
--- /dev/null
+++ b/include/with99/defres.h
@@ -0,0 +1,24 @@
+#ifndef WITH99_DEFRES_H
+#define WITH99_DEFRES_H
+
+#define WITH99_resource_type_Void_IMPL(var, _)    v(void*)
+#define WITH99_resource_init_Void_IMPL(var, init) v((var = init))
+#define WITH99_resource_free_Void_IMPL(var, ...)  v((free(var)))
+#define WITH99_resource_throws_Void_IMPL(...)     ML99_false()
+
+#define WITH99_resource_type_Memory_IMPL(var, type, _) v(type*)
+#define WITH99_resource_init_Memory_IMPL(var, _, init) v((var = init))
+#define WITH99_resource_free_Memory_IMPL(var, ...)     v((free(var)))
+#define WITH99_resource_throws_Memory_IMPL(...)        ML99_false()
+
+#define WITH99_resource_type_Adhoc_IMPL(var, type, _1, _2)   v(type)
+#define WITH99_resource_init_Adhoc_IMPL(var, _1, init, _2)   v((var = init))
+#define WITH99_resource_free_Adhoc_IMPL(var, _1, _2, deinit) v((deinit))
+#define WITH99_resource_throws_Adhoc_IMPL(...)               ML99_false()
+
+#define WITH99_resource_type_AdhocThrows_IMPL(var, type, _1, _2)   v(type)
+#define WITH99_resource_init_AdhocThrows_IMPL(var, _1, init, _2)   v((var = init))
+#define WITH99_resource_free_AdhocThrows_IMPL(var, _1, _2, deinit) v((deinit))
+#define WITH99_resource_throws_AdhocThrows_IMPL(...)               ML99_true()
+
+#endif