diff --git a/Dockerfile.in b/Dockerfile.in
index c2ecad6..44ff99e 100644
--- a/Dockerfile.in
+++ b/Dockerfile.in
@@ -1,4 +1,6 @@
-FROM debian:buster-slim
+ARG DOCKER_IMAGE=debian:bullseye-slim
+FROM $DOCKER_IMAGE
+
 MAINTAINER Matt McCormick "matt.mccormick@kitware.com"
 
 #include "common.debian"
diff --git a/common.debian b/common.debian
index 01d4d94..67027a1 100644
--- a/common.debian
+++ b/common.debian
@@ -36,10 +36,7 @@ RUN \
     xz-utils \
     zip \
     zlib1g-dev \
-#    python-is-python3 \
+    python-is-python3 \
     && apt-get clean autoclean --yes \
     && apt-get autoremove --yes \
     && rm -rf /var/lib/{apt,dpkg,cache,log}/
-
-RUN ln -s /usr/bin/python3 /usr/bin/python \
-    && ln -s /usr/bin/pip3 /usr/bin/pip
diff --git a/linux-x64-clang/Dockerfile.in b/linux-x64-clang/Dockerfile.in
index ed23eea..e362e65 100644
--- a/linux-x64-clang/Dockerfile.in
+++ b/linux-x64-clang/Dockerfile.in
@@ -1,9 +1,9 @@
 FROM dockcross/base:latest
 MAINTAINER Matt McCormick "matt.mccormick@kitware.com"
  # flang
-RUN echo "deb http://apt.llvm.org/buster/ llvm-toolchain-buster main" >> /etc/apt/sources.list \
-    && echo "deb-src http://apt.llvm.org/buster/ llvm-toolchain-buster main" >> /etc/apt/sources.list \
-    && wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key|sudo apt-key add - \
+RUN echo "deb http://apt.llvm.org/bullseye/ llvm-toolchain-bullseye main" >> /etc/apt/sources.list \
+    && echo "deb-src http://apt.llvm.org/bullseye/ llvm-toolchain-bullseye main" >> /etc/apt/sources.list \
+    && wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | apt-key add - \
     && apt-get update \
     && apt-get purge --autoremove -y gcc g++ software-properties-common \
     && apt-get -y install clang libc++-dev libc++abi-dev clang-format clang-tidy lldb \