diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 1d6bb49c5289746c2712f5f800c98305bc15d58a..6ab2c3565a2eab6cb5051c489fc8677822dba87f 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -47,6 +47,10 @@ Python 3.6 POCL MPI:
   - export PYOPENCL_TEST=portable
   - export EXTRA_INSTALL="numpy mako mpi4py pymetis"
   - export PYTEST_ADDOPTS="-k mpi"
+
+  # https://mpi4py.readthedocs.io/en/stable/mpi4py.run.html
+  - export PY_EXTRA_FLAGS="-m mpi4py.run"
+
   - curl -L -O -k https://gitlab.tiker.net/inducer/ci-support/raw/master/build-and-test-py-project.sh
   - ". ./build-and-test-py-project.sh"
   tags: