diff --git a/cabal.project b/cabal.project
index 2a5232cf9a8..579e7b89caa 100644
--- a/cabal.project
+++ b/cabal.project
@@ -13,8 +13,8 @@ repository cardano-haskell-packages
 -- See CONTRIBUTING for information about these, including some Nix commands
 -- you need to run if you change them
 index-state:
-  , hackage.haskell.org 2024-03-26T06:28:59Z
-  , cardano-haskell-packages 2024-05-14T16:00:00Z
+  , hackage.haskell.org 2024-05-25T09:09:57Z
+  , cardano-haskell-packages 2024-05-15T19:28:23Z
 
 packages:
   cardano-node
@@ -59,3 +59,6 @@ package plutus-scripts-bench
 -- temporary! Please read the section in CONTRIBUTING about updating dependencies.
 
 -- `smtp-mail` should depend on `crypton-connection` rather than `connection`!
+
+constraints:
+  io-classes-mtl < 0.1.2.0