diff --git a/.github/actions/fetch_ctk/action.yml b/.github/actions/fetch_ctk/action.yml
index 05076f730..7b8674abe 100644
--- a/.github/actions/fetch_ctk/action.yml
+++ b/.github/actions/fetch_ctk/action.yml
@@ -145,5 +145,6 @@ runs:
       run: |
         CUDA_PATH=$(realpath "./cuda_toolkit")
         echo "CUDA_PATH=${CUDA_PATH}" >> $GITHUB_ENV
+        echo "CUDA_HOME=${CUDA_PATH}" >> $GITHUB_ENV
         echo "${CUDA_PATH}/bin" >> $GITHUB_PATH
         echo "LD_LIBRARY_PATH=${LD_LIBRARY_PATH:-}:${CUDA_PATH}/lib" >> $GITHUB_ENV
diff --git a/.github/workflows/build-and-test.yml b/.github/workflows/build-and-test.yml
index 4eb0df753..bd7363c83 100644
--- a/.github/workflows/build-and-test.yml
+++ b/.github/workflows/build-and-test.yml
@@ -285,6 +285,9 @@ jobs:
         uses: actions/setup-python@v5
         with:
           python-version: ${{ matrix.python-version }}
+        env:
+          # we use self-hosted runners on which setup-python behaves weirdly...
+          AGENT_TOOLSDIRECTORY: "/opt/hostedtoolcache"
 
       - name: Set up mini CTK
         uses: ./.github/actions/fetch_ctk
@@ -306,8 +309,15 @@ jobs:
           pushd ./cuda_bindings
           pip install -r requirements.txt
           pytest -rxXs tests/
-          # TODO: enable cython tests
-          #pytest tests/cython
+          if [[ "${{ matrix.host-platform }}" == linux* ]]; then
+            # cython tests require gcc
+            apt install -y build-essential
+            bash tests/cython/build_tests.sh
+          elif [[ "${{ matrix.host-platform }}" == win* ]]; then
+            # TODO: enable this once win-64 runners are up 
+            exit 1
+          fi  
+          pytest -rxXs tests/cython
           popd
 
       - name: Run cuda.core tests