diff --git a/.github/workflows/ngsPETSc.yml b/.github/workflows/ngsPETSc.yml
index 5818ae3..821cfb3 100644
--- a/.github/workflows/ngsPETSc.yml
+++ b/.github/workflows/ngsPETSc.yml
@@ -39,34 +39,48 @@ jobs:
     timeout-minutes: 30
 
     steps:
-      - name: Check out repository code
-        uses: actions/checkout@v4
+      - uses: actions/checkout@v4
+        with:
+          # Download ngsPETSc into a subdirectory not called 'ngsPETSc' to make sure
+          # that the package installs correctly. Otherwise 'import ngsPETSc' may
+          # work even if the installation failed because it is a subdirectory.
+          path: ngspetsc-repo
+
+      - name: Create virtual environment
+        # pass '--system-site-packages' so ngsolve can be found
+        run: python3 -m venv --system-site-packages venv-ngspetsc
 
       - name: Install ngsPETSc
         run: |
-          python -m pip install .
+          . venv-ngspetsc/bin/activate
+          pip install --no-deps './ngspetsc-repo'
+          pip list
 
       - name: Run test suite in serial
         run: |
-          pytest -v tests/test_env.py
-          pytest -v tests/test_vec.py
-          pytest -v tests/test_mat.py
-          pytest -v tests/test_plex.py
-          pytest -v tests/test_ksp.py
-          pytest -v tests/test_pc.py
-          pytest -v tests/test_eps.py
-          pytest -v tests/test_snes.py
+          . venv-ngspetsc/bin/activate
+          cd ngspetsc-repo
+          python -m pytest -v tests/test_env.py
+          python -m pytest -v tests/test_vec.py
+          python -m pytest -v tests/test_mat.py
+          python -m pytest -v tests/test_plex.py
+          python -m pytest -v tests/test_ksp.py
+          python -m pytest -v tests/test_pc.py
+          python -m pytest -v tests/test_eps.py
+          python -m pytest -v tests/test_snes.py
 
       - name: Run test suite in parallel
         run: |
-          mpirun --allow-run-as-root -n 2 pytest -v --with-mpi tests/test_env.py
-          mpirun --allow-run-as-root -n 2 pytest -v --with-mpi tests/test_vec.py
-          mpirun --allow-run-as-root -n 2 pytest -v --with-mpi tests/test_mat.py
-          mpirun --allow-run-as-root -n 2 pytest -v --with-mpi tests/test_plex.py
-          mpirun --allow-run-as-root -n 2 pytest -v --with-mpi tests/test_ksp.py
-          mpirun --allow-run-as-root -n 2 pytest -v --with-mpi tests/test_pc.py
-          mpirun --allow-run-as-root -n 2 pytest -v --with-mpi tests/test_eps.py
-          mpirun --allow-run-as-root -n 2 pytest -v --with-mpi tests/test_snes.py
+          . venv-ngspetsc/bin/activate
+          cd ngspetsc-repo
+          mpirun --allow-run-as-root -n 2 python -m pytest -v --with-mpi tests/test_env.py
+          mpirun --allow-run-as-root -n 2 python -m pytest -v --with-mpi tests/test_vec.py
+          mpirun --allow-run-as-root -n 2 python -m pytest -v --with-mpi tests/test_mat.py
+          mpirun --allow-run-as-root -n 2 python -m pytest -v --with-mpi tests/test_plex.py
+          mpirun --allow-run-as-root -n 2 python -m pytest -v --with-mpi tests/test_ksp.py
+          mpirun --allow-run-as-root -n 2 python -m pytest -v --with-mpi tests/test_pc.py
+          mpirun --allow-run-as-root -n 2 python -m pytest -v --with-mpi tests/test_eps.py
+          mpirun --allow-run-as-root -n 2 python -m pytest -v --with-mpi tests/test_snes.py
 
   firedrake:
     runs-on: ubuntu-latest
diff --git a/tests/test_env.py b/tests/test_env.py
index a3c9f65..f755f8a 100644
--- a/tests/test_env.py
+++ b/tests/test_env.py
@@ -3,29 +3,37 @@
 In particular it will test for: petsc4py, PETSc, NGSolve and Netgen
 '''
 
-import petsc4py
-from petsc4py import PETSc
-
-import ngsolve as ngs
-from netgen.geom2d import unit_square
-from ngsolve import x,y
-
 def test_petsc4py():
     '''
     Testing that petsc4py can be imported correctly
     '''
+    import petsc4py
     assert petsc4py.get_config() != ""
 
+
 def  test_petsc():
     '''
     Testing that PETSc can be imported correctly
     '''
+    from petsc4py import PETSc
     assert PETSc.DECIDE == -1
 
+
+def test_netgen():
+    '''
+    Testing that NGSolve can be imported correctly
+    '''
+    from netgen.geom2d import unit_square
+    unit_square.GenerateMesh(maxh=0.1)
+
+
 def test_ngs():
     '''
     Testing that NGSolve can be imported correctly
     '''
+    from netgen.geom2d import unit_square
+    import ngsolve as ngs
+    from ngsolve import x,y
     mesh = ngs.Mesh(unit_square.GenerateMesh(maxh=0.1))
     coefficientFunction = x*(1-y)
     mip = mesh(0.2, 0.2)