diff --git a/stack.yaml b/stack.yaml
index e516041f..2d454af8 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,4 +1,4 @@
-resolver: lts-5.6
+resolver: lts-6.23
 packages:
   - ./yesod-core
   - ./yesod-static