diff --git a/.github/actions/load-fhir-xsd/action.yaml b/.github/actions/load-fhir-xsd/action.yaml
index e47b80e2..251a480b 100644
--- a/.github/actions/load-fhir-xsd/action.yaml
+++ b/.github/actions/load-fhir-xsd/action.yaml
@@ -96,6 +96,6 @@ runs:
         ls -l '${{ steps.vars.outputs.cache-dir}}'
         echo "::endgroup::"
         
-        echo "::group::Listing  files in '${{ steps.vars.outputs.version-xsd-cache-dir }}'"
+        echo "::group::Listing files in '${{ steps.vars.outputs.version-xsd-cache-dir }}'"
         ls -l '${{ steps.vars.outputs.version-xsd-cache-dir }}'
         echo "::endgroup::"
diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
index ef17d66e..f9c47000 100644
--- a/.github/workflows/tests.yaml
+++ b/.github/workflows/tests.yaml
@@ -93,6 +93,7 @@ jobs:
         uses: actions/checkout@v4
 
       - name: 'Load FHIR ${{ matrix.test-target }} Source'
+        id: fhir-source
         if: matrix.test-target != 'Core'
         uses: ./.github/actions/load-fhir-xsd
         with:
diff --git a/src/Config.php b/src/Config.php
index 80b84f4b..676a66e3 100644
--- a/src/Config.php
+++ b/src/Config.php
@@ -131,8 +131,8 @@ public static function fromArray(array $data): Config
         if (!isset($data['rootNamespace'])) {
             throw new \InvalidArgumentException('Key "rootNamespace" is required.');
         }
-        if (!isset($data['versions']) || !is_iterable($data['versions'])) {
-            throw new \InvalidArgumentException('Key "versions" is required and must be iterable.');
+        if (isset($data['versions']) && !is_iterable($data['versions'])) {
+            throw new \InvalidArgumentException('Key "versions" must be iterable.');
         }
         if (isset($data['logger']) && !($data['logger'] instanceof LoggerInterface)) {
             throw new \InvalidArgumentException('Key "logger" must be an instance of Psr\Log\LoggerInterface');