diff --git a/Dockerfile b/Dockerfile
index 8526e29..2ebfb1a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -10,6 +10,12 @@ ENV LANG=C.UTF-8 \
 # * update-alternatives needs ../man1/
 # * ca-certificates for fetching from HTTPS repos
 RUN mkdir -p /usr/share/man/man1 \
+	&& echo "deb http://deb.debian.org/debian sid main" >> /etc/apt/sources.list \
+	&& printf "Package: *\nPin: release o=Debian,a=sid\nPin-Priority: -10\n" \
+             > /etc/apt/preferences.d/debian-sid.pref \
+	&& echo "deb http://deb.debian.org/debian experimental main" >> /etc/apt/sources.list \
+	&& printf "Package: *\nPin: release o=Debian,a=experimental\nPin-Priority: -100\n" \
+             > /etc/apt/preferences.d/debian-experimental.pref \
 	&& apt-get update \
 	&& apt-get -qy upgrade \
 	&& apt-get -qy dist-upgrade \