diff --git a/etc/diskspace/clean-old-stack-libs.sh b/etc/diskspace/clean-old-stack-libs.sh
index 2a3554f4..ac768017 100755
--- a/etc/diskspace/clean-old-stack-libs.sh
+++ b/etc/diskspace/clean-old-stack-libs.sh
@@ -10,4 +10,4 @@ fi
 cd ~/stackage/automated/work/$1/unpack-dir/.stack-work/install/x86_64-linux/*/*/lib/x86_64-linux-ghc-*
 pwd
 
-stack --resolver nightly-2020-07-04 script ~/stackage/etc/diskspace/remove-old-stack-work-libs.hs
+stack --resolver lts-18.6 script ~/stackage/etc/diskspace/remove-old-stack-work-libs.hs
diff --git a/etc/diskspace/remove-old-stack-work-libs.hs b/etc/diskspace/remove-old-stack-work-libs.hs
index d26fcd06..0b8f2523 100644
--- a/etc/diskspace/remove-old-stack-work-libs.hs
+++ b/etc/diskspace/remove-old-stack-work-libs.hs
@@ -1,5 +1,5 @@
 #!/usr/bin/env stack
--- stack --resolver nightly script
+-- stack --resolver lts-18.6 script
 
 -- Utility to remove old libs installed under .stack-work/ to save diskspace