diff --git a/.github/workflows/haskell-ci.yml b/.github/workflows/haskell-ci.yml
index 377723cd1..c9f51ccc8 100644
--- a/.github/workflows/haskell-ci.yml
+++ b/.github/workflows/haskell-ci.yml
@@ -28,9 +28,9 @@ jobs:
     strategy:
       matrix:
         include:
-          - compiler: ghc-9.6.1
+          - compiler: ghc-9.6.4
             compilerKind: ghc
-            compilerVersion: 9.6.1
+            compilerVersion: 9.6.4
             setup-method: ghcup
             allow-failure: false
           # - compiler: ghc-9.4.4
diff --git a/hgeometry/hgeometry.cabal b/hgeometry/hgeometry.cabal
index e02593e2f..ee1446307 100644
--- a/hgeometry/hgeometry.cabal
+++ b/hgeometry/hgeometry.cabal
@@ -30,7 +30,7 @@ data-files:
 tested-with:
     GHC == 9.2.5
   , GHC == 9.4.4
-  , GHC == 9.6.1
+  , GHC == 9.6.4
 
 source-repository head
   type:     git