diff --git a/.github/workflows/tests-tox.yaml b/.github/workflows/tests-tox.yaml
index f011d89c..d389fe71 100644
--- a/.github/workflows/tests-tox.yaml
+++ b/.github/workflows/tests-tox.yaml
@@ -49,6 +49,7 @@ jobs:
       - name: Install Mac OS dependencies
         if: runner.os == 'macOS'
         run: |
+          brew install r
           Rscript --no-environ -e "install.packages('BiocManager', repos='https://cloud.r-project.org'); BiocManager::install('DNAcopy')"
       - name: Install test runner tools
         run: pip install flake8 pytest tox