diff --git a/Makefile b/Makefile
index 8a55b5544..72e25f4cc 100644
--- a/Makefile
+++ b/Makefile
@@ -3,7 +3,7 @@ all: docker-images
 
 DOCKER := sudo docker
 
-docker-images: gcc-explorer-image d-explorer-image rust-explorer-image
+docker-images: gcc-explorer-image d-explorer-image rust-explorer-image gcc-explorer-image-1204
 
 .s3cfg: config.py
 	echo 'from config import *; print "[default]\\naccess_key = {}\\nsecret_key={}\\n" \
@@ -11,6 +11,8 @@ docker-images: gcc-explorer-image d-explorer-image rust-explorer-image
 
 docker/gcc-explorer/.s3cfg: .s3cfg
 	cp $< $@
+docker/gcc-explorer-1204/.s3cfg: .s3cfg
+	cp $< $@
 docker/d-explorer/.s3cfg: .s3cfg
 	cp $< $@
 docker/rust-explorer/.s3cfg: .s3cfg
@@ -19,6 +21,9 @@ docker/rust-explorer/.s3cfg: .s3cfg
 gcc-explorer-image: docker/gcc-explorer/.s3cfg
 	$(DOCKER) build -t "mattgodbolt/gcc-explorer:gcc" docker/gcc-explorer
 
+gcc-explorer-image-1204: docker/gcc-explorer-1204/.s3cfg
+	$(DOCKER) build -t "mattgodbolt/gcc-explorer:gcc1204" docker/gcc-explorer-1204
+
 d-explorer-image: docker/d-explorer/.s3cfg
 	$(DOCKER) build -t "mattgodbolt/gcc-explorer:d" docker/d-explorer
 
diff --git a/docker/d-explorer/run.sh b/docker/d-explorer/run.sh
index 63f3bd35a..352bf9858 100755
--- a/docker/d-explorer/run.sh
+++ b/docker/d-explorer/run.sh
@@ -1,8 +1,9 @@
 #!/bin/bash
 
 set -ex
+. /site.sh
 
-git clone -b release --depth 1 https://github.com/mattgodbolt/gcc-explorer.git /gcc-explorer
+git clone -b ${BRANCH} --depth 1 https://github.com/mattgodbolt/gcc-explorer.git /gcc-explorer
 cd /gcc-explorer
 make prereqs GDC=/usr/bin/gdc-4.9
 nodejs app.js --env amazon-d
diff --git a/docker/gcc-explorer-1204/Dockerfile b/docker/gcc-explorer-1204/Dockerfile
new file mode 100644
index 000000000..53f4a7100
--- /dev/null
+++ b/docker/gcc-explorer-1204/Dockerfile
@@ -0,0 +1,56 @@
+FROM ubuntu:12.04
+MAINTAINER Matt Godbolt <matt@godbolt.org>
+
+RUN apt-get -y update && apt-get install -y python-software-properties
+RUN add-apt-repository -y ppa:chris-lea/node.js && add-apt-repository -y ppa:ubuntu-toolchain-r/test
+
+RUN apt-get -y update && apt-get install -y \
+    curl \
+    git \
+    make \
+    nodejs \
+    s3cmd \
+    clang \
+    g++ \
+    g++-4.4 \
+    g++-4.5 \
+    g++-4.5-arm-linux-gnueabi \
+    g++-4.6 \
+    g++-4.6-arm-linux-gnueabi \
+    g++-4.7 \
+    g++-4.7-multilib \
+    g++-4.8 \
+    g++-4.8-multilib \
+    gcc-4.4 \
+    gcc-4.5 \
+    gcc-4.6 \
+    gcc-4.7-base \
+    gcc-4.7-multilib \
+    gcc-4.8 \
+    gcc-4.8-multilib \
+    gcc-avr \
+    gcc-msp430 \
+    gcc-snapshot
+
+RUN mkdir -p /root
+RUN mkdir -p /root/.ssh
+COPY .s3cfg /root/
+COPY known_hosts /root/.ssh/
+COPY compilers.sh /root/
+RUN bash /root/compilers.sh
+RUN rm /root/compilers.sh
+RUN rm /root/.s3cfg
+RUN apt-get purge -y curl s3cmd openjdk-6-jre-lib
+RUN apt-get autoremove -y
+RUN apt-get clean
+RUN rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
+
+#####################
+RUN useradd gcc-user && mkdir -p /gcc-explorer /home/gcc-user && chown gcc-user /gcc-explorer && chown gcc-user /home/gcc-user
+ENV HOME /home/gcc-user
+COPY run.sh /
+
+USER gcc-user
+WORKDIR /gcc-explorer
+EXPOSE 20480
+CMD ["/run.sh"]
diff --git a/docker/gcc-explorer-1204/compilers.sh b/docker/gcc-explorer-1204/compilers.sh
new file mode 100644
index 000000000..2034c719d
--- /dev/null
+++ b/docker/gcc-explorer-1204/compilers.sh
@@ -0,0 +1,20 @@
+#/bin/bash
+
+set -e
+cd /opt
+
+for compiler in clang-3.2.tar.gz \
+    clang-3.3.tar.gz \
+    gcc-4.9.0-0909-concepts.tar.gz \
+    gcc-4.9.0-with-concepts.tar.gz \
+    gcc-4.9.0.tar.gz \
+    intel.tar.gz \
+    ; do
+    s3cmd --config /root/.s3cfg get s3://gcc-explorer/opt/$compiler /opt/$compiler
+    tar zxf $compiler
+    rm $compiler
+done
+
+curl http://llvm.org/releases/3.4.1/clang+llvm-3.4.1-x86_64-unknown-ubuntu12.04.tar.xz | tar Jxf -
+
+find /opt -executable -type f | xargs strip || true
diff --git a/docker/gcc-explorer-1204/known_hosts b/docker/gcc-explorer-1204/known_hosts
new file mode 100644
index 000000000..cc3b9fb8c
--- /dev/null
+++ b/docker/gcc-explorer-1204/known_hosts
@@ -0,0 +1,2 @@
+|1|6kkg4vXFndu74Cif5Oz9098PsY4=|k0sy2nylJdzYTwQK+aKmITvX8S8= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAq2A7hRGmdnm9tUDbO9IDSwBK6TbQa+PXYPCPy6rbTrTtw7PHkccKrpp0yVhp5HdEIcKr6pLlVDBfOLX9QUsyCOV0wzfjIJNlGEYsdlLJizHhbn2mUjvSAHQqZETYP81eFzLQNnPHt4EVVUh7VfDESU84KezmD5QlWpXLmvU31/yMf+Se8xhHTvKSCZIFImWwoG6mbUoWf9nzpIoaSjB+weqqUUmpaaasXVal72J+UX2B+2RPW3RcT0eOzQgqlJL3RKrTJvdsjE3JEAvGq3lGHSZXy28G3skua2SmVi/w4yCE6gbODqnTWlg7+wC604ydGXA8VJiS5ap43JXiUFFAaQ==
+|1|9zKzfbCf91lj6RBfxx8gmxHV7Lc=|9JCgnqPKdeIaFvFF0tijjEgBWOk= ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAq2A7hRGmdnm9tUDbO9IDSwBK6TbQa+PXYPCPy6rbTrTtw7PHkccKrpp0yVhp5HdEIcKr6pLlVDBfOLX9QUsyCOV0wzfjIJNlGEYsdlLJizHhbn2mUjvSAHQqZETYP81eFzLQNnPHt4EVVUh7VfDESU84KezmD5QlWpXLmvU31/yMf+Se8xhHTvKSCZIFImWwoG6mbUoWf9nzpIoaSjB+weqqUUmpaaasXVal72J+UX2B+2RPW3RcT0eOzQgqlJL3RKrTJvdsjE3JEAvGq3lGHSZXy28G3skua2SmVi/w4yCE6gbODqnTWlg7+wC604ydGXA8VJiS5ap43JXiUFFAaQ==
diff --git a/docker/gcc-explorer-1204/run.sh b/docker/gcc-explorer-1204/run.sh
new file mode 100755
index 000000000..267ac1380
--- /dev/null
+++ b/docker/gcc-explorer-1204/run.sh
@@ -0,0 +1,10 @@
+#!/bin/bash
+
+set -ex
+
+. /site.sh
+
+git clone -b ${BRANCH} --depth 1 https://github.com/mattgodbolt/gcc-explorer.git /gcc-explorer
+cd /gcc-explorer
+make prereqs
+nodejs app.js --env amazon1204
diff --git a/docker/gcc-explorer/Dockerfile b/docker/gcc-explorer/Dockerfile
index d79cf7011..f9f3cdebc 100644
--- a/docker/gcc-explorer/Dockerfile
+++ b/docker/gcc-explorer/Dockerfile
@@ -1,7 +1,7 @@
-FROM ubuntu:12.04
+FROM ubuntu:14.04
 MAINTAINER Matt Godbolt <matt@godbolt.org>
 
-RUN apt-get -y update && apt-get install -y python-software-properties
+RUN apt-get -y update && apt-get install -y python-software-properties software-properties-common
 RUN add-apt-repository -y ppa:chris-lea/node.js && add-apt-repository -y ppa:ubuntu-toolchain-r/test
 
 RUN apt-get -y update && apt-get install -y \
@@ -10,27 +10,11 @@ RUN apt-get -y update && apt-get install -y \
     make \
     nodejs \
     s3cmd \
-    clang \
-    g++ \
-    g++-4.4 \
-    g++-4.5 \
-    g++-4.5-arm-linux-gnueabi \
-    g++-4.6 \
-    g++-4.6-arm-linux-gnueabi \
-    g++-4.7 \
-    g++-4.7-multilib \
+    clang-3.5 \
     g++-4.8 \
-    g++-4.8-multilib \
-    gcc-4.4 \
-    gcc-4.5 \
-    gcc-4.6 \
-    gcc-4.7-base \
-    gcc-4.7-multilib \
-    gcc-4.8 \
-    gcc-4.8-multilib \
-    gcc-avr \
-    gcc-msp430 \
-    gcc-snapshot
+    g++-4.8-powerpc-linux-gnu \
+    g++-arm-linux-gnueabihf \
+    g++-aarch64-linux-gnu
 
 RUN mkdir -p /root
 RUN mkdir -p /root/.ssh
diff --git a/docker/gcc-explorer/compilers.sh b/docker/gcc-explorer/compilers.sh
index 2034c719d..f083d8caf 100644
--- a/docker/gcc-explorer/compilers.sh
+++ b/docker/gcc-explorer/compilers.sh
@@ -3,18 +3,4 @@
 set -e
 cd /opt
 
-for compiler in clang-3.2.tar.gz \
-    clang-3.3.tar.gz \
-    gcc-4.9.0-0909-concepts.tar.gz \
-    gcc-4.9.0-with-concepts.tar.gz \
-    gcc-4.9.0.tar.gz \
-    intel.tar.gz \
-    ; do
-    s3cmd --config /root/.s3cfg get s3://gcc-explorer/opt/$compiler /opt/$compiler
-    tar zxf $compiler
-    rm $compiler
-done
-
-curl http://llvm.org/releases/3.4.1/clang+llvm-3.4.1-x86_64-unknown-ubuntu12.04.tar.xz | tar Jxf -
-
 find /opt -executable -type f | xargs strip || true
diff --git a/docker/gcc-explorer/run.sh b/docker/gcc-explorer/run.sh
index 55ab6681c..f4640d6b3 100755
--- a/docker/gcc-explorer/run.sh
+++ b/docker/gcc-explorer/run.sh
@@ -2,7 +2,9 @@
 
 set -ex
 
-git clone -b release --depth 1 https://github.com/mattgodbolt/gcc-explorer.git /gcc-explorer
+. /site.sh
+
+git clone -b ${BRANCH} --depth 1 https://github.com/mattgodbolt/gcc-explorer.git /gcc-explorer
 cd /gcc-explorer
 make prereqs
 nodejs app.js --env amazon
diff --git a/docker/rust-explorer/run.sh b/docker/rust-explorer/run.sh
index b51cc6186..4642fd665 100755
--- a/docker/rust-explorer/run.sh
+++ b/docker/rust-explorer/run.sh
@@ -2,7 +2,9 @@
 
 set -ex
 
-git clone -b release --depth 1 https://github.com/mattgodbolt/gcc-explorer.git /gcc-explorer
+. /site.sh
+
+git clone -b ${BRANCH} --depth 1 https://github.com/mattgodbolt/gcc-explorer.git /gcc-explorer
 cd /gcc-explorer
 make prereqs
 nodejs app.js --env amazon-rust
diff --git a/gcc-explorer.conf b/gcc-explorer.conf
index 82621c1ef..e0872936c 100644
--- a/gcc-explorer.conf
+++ b/gcc-explorer.conf
@@ -20,6 +20,8 @@ script
   set -e
   HOME=/root
   export HOME
+  DEV_MODE=0
+  export DEV_MODE
   mkfifo /tmp/gcc-explorer-log
   ( logger -t gcc </tmp/gcc-explorer-log & )
   exec >/tmp/gcc-explorer-log
diff --git a/run_site.sh b/run_site.sh
index 5abbd0000..aac0e2fa8 100755
--- a/run_site.sh
+++ b/run_site.sh
@@ -2,28 +2,40 @@
 
 set -ex
 
+DIR=$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )
 SUDO=sudo
 if [[ $UID = 0 ]]; then
     SUDO=
 fi
 
-$SUDO docker pull mattgodbolt/gcc-explorer
+EXTERNAL_PORT=80
+CONFIG_FILE=${DIR}/site-prod.sh
+if [[ ${DEV_MODE=1} = 1 ]]; then
+    EXTERNAL_PORT=8000
+    CONFIG_FILE=${DIR}/site-dev.sh
+else
+    $SUDO docker pull mattgodbolt/gcc-explorer
+fi
+
+ALL="gcc gcc1204 d rust nginx"
+$SUDO docker stop ${ALL} || true
+$SUDO docker rm ${ALL} || true
 
-$SUDO docker stop gcc d rust nginx || true
-$SUDO docker rm gcc d rust nginx || true
+CFG="-v ${CONFIG_FILE}:/site.sh:ro"
 
-GCC=$(sudo docker run --name gcc -d -p 10240:10240 mattgodbolt/gcc-explorer:gcc)
-D=$(sudo docker run --name d -d -p 10241:10241 mattgodbolt/gcc-explorer:d)
-RUST=$(sudo docker run --name rust -d -p 10242:10242 mattgodbolt/gcc-explorer:rust)
+$SUDO docker run --name gcc1204 ${CFG} -d -p 20480:20480 mattgodbolt/gcc-explorer:gcc1204
+$SUDO docker run --name gcc ${CFG} --link gcc1204:gcc1204 -d -p 10240:10240 mattgodbolt/gcc-explorer:gcc
+$SUDO docker run --name d ${CFG} -d -p 10241:10241 mattgodbolt/gcc-explorer:d
+$SUDO docker run --name rust ${CFG} -d -p 10242:10242 mattgodbolt/gcc-explorer:rust
 
-trap "$SUDO docker stop $GCC $D $RUST" SIGINT SIGTERM SIGPIPE
+trap "$SUDO docker stop ${ALL}" SIGINT SIGTERM SIGPIPE
 
 $SUDO docker run \
-    -p 80:80 \
+    -p ${EXTERNAL_PORT}:80 \
     --name nginx \
     --volumes-from gcc \
     -v /var/log/nginx:/var/log/nginx \
-    -v /home/ubuntu:/var/www \
-    -v $(pwd)/nginx:/etc/nginx/sites-enabled \
+    -v /home/ubuntu:/var/www:ro \
+    -v $(pwd)/nginx:/etc/nginx/sites-enabled:ro \
     --link gcc:gcc --link d:d --link rust:rust \
     dockerfile/nginx
diff --git a/site-dev.sh b/site-dev.sh
new file mode 100644
index 000000000..e6fb04e5c
--- /dev/null
+++ b/site-dev.sh
@@ -0,0 +1,2 @@
+# Sourced when running in development mode
+export BRANCH=master
diff --git a/site-prod.sh b/site-prod.sh
new file mode 100644
index 000000000..06aeed68b
--- /dev/null
+++ b/site-prod.sh
@@ -0,0 +1,2 @@
+# Sourced when loaded in production
+export BRANCH=release