diff --git a/docker/proton.Dockerfile.in b/docker/proton.Dockerfile.in
index bac3d812..95f06782 100644
--- a/docker/proton.Dockerfile.in
+++ b/docker/proton.Dockerfile.in
@@ -59,6 +59,7 @@ RUN apt-get install -y \
   libxpresent-dev:i386 \
   libopenblas-dev \
   libopenblas-dev:i386 \
+  python3-mako \
   python3-pefile \
   libcapstone-dev \
   libcapstone-dev:i386 \