diff --git a/.github/workflows/R-CMD-check.yaml b/.github/workflows/R-CMD-check.yaml
index 304910032..59f7a0aa6 100644
--- a/.github/workflows/R-CMD-check.yaml
+++ b/.github/workflows/R-CMD-check.yaml
@@ -20,11 +20,10 @@ jobs:
       matrix:
         config:
           - {os: windows-latest, r: 'release'}
-          # - {os: macOS-latest, r: 'release'}
-          # - {os: macOS-latest, r: 'devel'}
+          - {os: macOS-latest, r: 'release'}
           - {os: ubuntu-latest,   r: 'devel', http-user-agent: 'release'}
-          # - {os: ubuntu-latest,   r: 'release'}
-          # - {os: ubuntu-latest,   r: 'oldrel-1'}
+          - {os: ubuntu-latest,   r: 'release'}
+          - {os: ubuntu-latest,   r: 'oldrel-1'}
 
     env:
       R_REMOTES_NO_ERRORS_FROM_WARNINGS: true