diff --git a/stack.yaml b/stack.yaml
index 385b4d049fc41991b3cc6eec995e757f2432195e..ff12a4f500c2fd120768b883c5f1b1a5650f9f1b 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -15,7 +15,7 @@
 # resolver:
 #  name: custom-snapshot
 #  location: "./custom-snapshot.yaml"
-resolver: lts-12.18
+resolver: lts-12.20
 
 # User packages to be built.
 # Various formats can be used as shown in the example below.