diff --git a/stack.yaml b/stack.yaml
index 85f2dbe..245a3e7 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -3,7 +3,7 @@ packages:
   - libarchive
   - libarchive-clib
   - zlib-clib
-resolver: lts-21.24
+resolver: lts-20.26
 ghc-options: {"$locals": -ddump-to-file -ddump-hi}
 flags:
   libarchive: