diff --git a/.github/workflows/elixir-ci-reusable.yml b/.github/workflows/elixir-ci-reusable.yml
index f1f6201b..37aff35b 100644
--- a/.github/workflows/elixir-ci-reusable.yml
+++ b/.github/workflows/elixir-ci-reusable.yml
@@ -102,7 +102,7 @@ jobs:
     name: Compile + test
     runs-on: ${{ inputs.runs-on }}
     # Guard on mix.exs so the wrapper is safe to add unconditionally.
-    if: hashFiles(format('{0}/mix.exs', inputs.working_directory)) != ''
+    if: ${{ hashFiles(format('{0}/mix.exs', inputs.working_directory)) != '' }}
     permissions:
       contents: read
     env: