diff --git a/.github/workflows/R-CMD-as-cran-check.yaml b/.github/workflows/R-CMD-as-cran-check.yaml
index 8040a48..c59ab94 100644
--- a/.github/workflows/R-CMD-as-cran-check.yaml
+++ b/.github/workflows/R-CMD-as-cran-check.yaml
@@ -12,15 +12,17 @@ jobs:
     if: "! contains(github.event.head_commit.message, '[ci skip]')"
     runs-on: ${{ matrix.config.os }}
     name: ${{ matrix.config.os }} (${{ matrix.config.r }})
-    fail-fast: false
-    matrix:
-      config:
-        - {os: macos-latest,   r: 'release'}
-        #- {os: macos-13-xlarge,   r: 'release'}
-        #- {os: windows-latest, r: 'release'}
-        - {os: ubuntu-latest,   r: 'devel', http-user-agent: 'release'}
-        - {os: ubuntu-latest,   r: 'release'}
-        - {os: ubuntu-latest,   r: 'oldrel-1'}
+    
+    strategy:
+      fail-fast: false
+      matrix:
+        config:
+          - {os: macos-latest,   r: 'release'}
+          #- {os: macos-13-xlarge,   r: 'release'}
+          #- {os: windows-latest, r: 'release'}
+          - {os: ubuntu-latest,   r: 'devel', http-user-agent: 'release'}
+          - {os: ubuntu-latest,   r: 'release'}
+          - {os: ubuntu-latest,   r: 'oldrel-1'}
 
     env:
       GITHUB_PAT: ${{ secrets.GITHUB_TOKEN }}