diff --git a/contrib/Dockerfile.builder b/contrib/Dockerfile.builder
index 737088071..5d4a0d6c7 100644
--- a/contrib/Dockerfile.builder
+++ b/contrib/Dockerfile.builder
@@ -13,6 +13,7 @@ RUN apt-get -qq update && \
 	automake \
 	clang \
 	cppcheck \
+	docbook-xml \
 	shellcheck \
 	eatmydata \
 	software-properties-common \
@@ -34,6 +35,7 @@ RUN apt-get -qq update && \
 	shellcheck \
 	libxml2-utils \
 	wget \
+	xsltproc \
 	zlib1g-dev && \
 	rm -rf /var/lib/apt/lists/*
 
diff --git a/contrib/Dockerfile.builder.i386 b/contrib/Dockerfile.builder.i386
index 478c00259..928425353 100644
--- a/contrib/Dockerfile.builder.i386
+++ b/contrib/Dockerfile.builder.i386
@@ -13,6 +13,7 @@ RUN apt-get -qq update && \
 	automake \
 	clang \
 	cppcheck \
+	docbook-xml \
 	shellcheck \
 	eatmydata \
 	software-properties-common \
@@ -34,6 +35,7 @@ RUN apt-get -qq update && \
 	shellcheck \
 	libxml2-utils \
 	wget \
+	xsltproc \
 	zlib1g-dev && \
 	rm -rf /var/lib/apt/lists/*