diff --git a/.github/workflows/R-CMD-check.yaml b/.github/workflows/R-CMD-check.yaml
index 179183d27..ff281cae3 100644
--- a/.github/workflows/R-CMD-check.yaml
+++ b/.github/workflows/R-CMD-check.yaml
@@ -235,6 +235,10 @@ jobs:
           rcmdcheck::rcmdcheck(args = check_args, build_args = build_args, error_on = error_on, check_dir = "check")
         shell: Rscript {0}
 
+      - name: Setup tmate session
+        if: ${{ failure() }}
+        uses: mxschmitt/action-tmate@v3
+
       - name: Check UBSAN output
         if: contains(matrix.config.flags, 'ubsan')
         # NB: xargs -r only works in GNU, so not on MacOS.