diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 25e262d074551a616c5d65ad5874871afb936137..bcf5fc62304ec74271670e51d527919bd1c60b47 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -34,6 +34,10 @@ jobs:
                 sudo apt-get update
                 sudo apt-get install openmpi-bin libopenmpi-dev
                 CONDA_ENVIRONMENT=.test-conda-env-py3.yml
+                
+                # https://github.com/inducer/grudge/pull/19
+                CISUPPORT_PARALLEL_PYTEST=no
+                
                 curl -L -O -k https://gitlab.tiker.net/inducer/ci-support/raw/master/build-and-test-py-project-within-miniconda.sh
                 . ./build-and-test-py-project-within-miniconda.sh