diff --git a/.github/workflows/stack.yml b/.github/workflows/stack.yml
index 430f08be3..f353ff423 100644
--- a/.github/workflows/stack.yml
+++ b/.github/workflows/stack.yml
@@ -12,6 +12,8 @@ jobs:
       fail-fast: false
       matrix:
         include:
+          - resolver: lts-16  # GHC 8.6
+            yaml: stack.yaml
           - resolver: lts-16  # GHC 8.8
             yaml: stack-master.yaml
           - resolver: lts-18  # GHC 8.10