diff --git a/build-unit-test-docker.sh b/build-unit-test-docker.sh
index 6031fac..b0cc4a3 100755
--- a/build-unit-test-docker.sh
+++ b/build-unit-test-docker.sh
@@ -71,6 +71,7 @@
 
 RUN easy_install pip
 RUN pip install inflection
+RUN pip install pycodestyle
 
 RUN wget http://ftpmirror.gnu.org/autoconf-archive/autoconf-archive-2016.09.16.tar.xz
 RUN tar -xJf autoconf-archive-2016.09.16.tar.xz