diff --git a/stack.yaml b/stack.yaml
index c73566f..2819e28 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -15,7 +15,7 @@
 # resolver:
 #  name: custom-snapshot
 #  location: "./custom-snapshot.yaml"
-resolver: lts-14.20
+resolver: lts-14.21
 
 # User packages to be built.
 # Various formats can be used as shown in the example below.