diff --git a/.dockerignore b/.dockerignore
index ac48b1cb..5ce6d9ad 100644
--- a/.dockerignore
+++ b/.dockerignore
@@ -3,3 +3,4 @@
 .tox/
 .vagrant/
 .vscode/
+**/*.pyc
diff --git a/docker/Dockerfile-tests b/docker/Dockerfile-tests
index 66915e3a..c54d9028 100644
--- a/docker/Dockerfile-tests
+++ b/docker/Dockerfile-tests
@@ -48,7 +48,7 @@ RUN yum -y install \
     && yum clean all
 # We currently require newer versions of these Python packages for the tests.
 # more-itertools is required by pytest, but versions 6.0.0 and up aren't Python 2 compatible
-RUN pip install --upgrade flask-sqlalchemy pytest flake8 tox pip "more-itertools<6.0.0"
+RUN pip install --upgrade flask-sqlalchemy "pytest<5.0" flake8 tox pip "more-itertools<6.0.0"
 VOLUME /src
 WORKDIR /src
 ENTRYPOINT ["docker/test.sh"]