diff --git a/stack.yaml b/stack.yaml
index b928ab330e7ddce07916bf4db3ab9c9839fae666..9479299413ecef4d8ad030d8a4f2b904d9415a6e 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -15,7 +15,7 @@
 # resolver:
 #  name: custom-snapshot
 #  location: "./custom-snapshot.yaml"
-resolver: lts-14.14
+resolver: lts-14.21
 
 # User packages to be built.
 # Various formats can be used as shown in the example below.