diff --git a/cryptol.cabal b/cryptol.cabal
index e926534a6..0da6bb66b 100644
--- a/cryptol.cabal
+++ b/cryptol.cabal
@@ -27,7 +27,7 @@ source-repository this
   type:     git
   location: https://github.com/GaloisInc/cryptol.git
   -- add a tag on release branches
-  -- tag:
+  tag:      3.1.0
 
 
 flag static