diff --git a/ron-schema.cabal b/ron-schema.cabal
--- a/ron-schema.cabal
+++ b/ron-schema.cabal
@@ -1,7 +1,7 @@
 cabal-version:  2.2
 
 name:           ron-schema
-version:        0.9
+version:        0.9.1
 
 bug-reports:    https://github.com/ff-notes/ron/issues
 category:       Distributed Systems, Protocol, Database
@@ -40,8 +40,8 @@
         text,
         transformers,
         -- project
-        ron,
-        ron-rdt
+        ron     >= 0.9,
+        ron-rdt >= 0.9.1,
     exposed-modules:
         RON.Schema
         RON.Schema.TH