diff --git a/test/.docker/Dockerfile b/test/.docker/Dockerfile
index 1634ab9f5d2b8aa40c22240d6e88ae66d2eb7c48..7affafd8cca5c806780f76c9deaac9e5163bc741 100644
--- a/test/.docker/Dockerfile
+++ b/test/.docker/Dockerfile
@@ -9,4 +9,6 @@ RUN apt-get install -y python3-pip
 COPY doc/requirements.txt requirements.txt
 RUN pip3 install -r requirements.txt
 
+RUN echo "deb http://deb.debian.org/debian buster-backports main" > /etc/apt/sources.list.d/buster-backports.list
+RUN apt-get update
 RUN apt-get install -y clang-format-11