etc/settings

--- a/etc/settings	Fri Dec 28 19:06:33 2018 +0100
+++ b/etc/settings	Fri Dec 28 19:01:35 2018 +0100
@@ -153,9 +153,9 @@
 
 ISABELLE_STACK_ROOT="$ISABELLE_HOME_USER/stack"
 
-ISABELLE_STACK_RESOLVER="lts-13.0"
+ISABELLE_STACK_RESOLVER="lts-12.25"
 
-ISABELLE_GHC_VERSION="ghc-8.6.3"
+ISABELLE_GHC_VERSION="ghc-8.4.4"
 
 
 ###