diff --git a/.github/workflows/lean_action_ci.yml b/.github/workflows/lean_action_ci.yml
index ec930b8ca..1053d8a53 100644
--- a/.github/workflows/lean_action_ci.yml
+++ b/.github/workflows/lean_action_ci.yml
@@ -14,6 +14,10 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
+      - name: Set TEST_ARGS manually
+        run: |
+          echo "TEST_ARGS='--wfail --iofail'" >> $GITHUB_ENV
+        shell: bash
       - uses: leanprover/lean-action@v1
         with:
           build-args: "--wfail --iofail"
diff --git a/CslibTests/DFA.lean b/CslibTests/DFA.lean
index f78e47c0d..3fc2af1f6 100644
--- a/CslibTests/DFA.lean
+++ b/CslibTests/DFA.lean
@@ -17,6 +17,7 @@ inductive Floor where
 | two
 deriving DecidableEq
 
+@[implicit_reducible]
 def Floor.fintype : Fintype Floor := {
   elems := {.one, .two}
   complete floor := by grind [Floor]
@@ -29,6 +30,7 @@ inductive Direction where
 | down
 deriving DecidableEq
 
+@[implicit_reducible]
 def Direction.fintype : Fintype Direction := {
   elems := {.up, .down}
   complete dir := by grind [Direction]