1 files changed, 4 insertions, 1 deletions

diff --git a/stack.yaml b/stack.yaml
index a1a2869..ca6d0ad 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -1,5 +1,8 @@
 packages:
 - '.'
-resolver: lts-9.0
+resolver: lts-12.10
 extra-deps:
+- graphviz-2999.20.0.2
+- posix-pty-0.2.1.1
+- sandi-0.4.2
 explicit-setup-deps: