diff --git a/contrib/arc b/contrib/arc
--- a/contrib/arc
+++ b/contrib/arc
@@ -12,6 +12,8 @@
 #   Image:          nasqueron/arcanist
 #   -------------------------------------------------------------
 
+BASE_IMAGE=nasqueron/arcanist
+
 #   -------------------------------------------------------------
 #   Parse arguments
 #   - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
@@ -53,7 +55,7 @@
 	BUILD_DIR=$(mktemp -d -t arc-build-XXXXXXXXXX)
 	pushd "$BUILD_DIR" > /dev/null || exit 1
 	>&2 echo "🔨 Building user-specific image $IMAGE for $USER"
-	echo "FROM nasqueron/arcanist" > Dockerfile
+	echo "FROM $BASE_IMAGE" > Dockerfile
 	echo "RUN groupadd -r $USER -g $GID && mkdir /home/$USER && useradd -u $UID -r -g $USER -d /home/$USER -s /bin/bash $USER && cp /root/.bashrc /home/$USER/ && chown -R $USER:$USER /home/$USER && ln -s /opt/config/gitconfig /home/$USER/.gitconfig && ln -s /opt/config/arcrc /home/$USER/.arcrc" >> Dockerfile
 	docker build -t "$IMAGE" .
 	popd > /dev/null
@@ -64,10 +66,10 @@
 test -v $GID && GID=$(id -g)
 
 if [ $UID -eq 0 ]; then
-	IMAGE=nasqueron/arcanist
+	IMAGE=$BASE_IMAGE
 	CONTAINER_USER_HOME=/root
 else
-	IMAGE=nasqueron/arcanist:$UID-$GID
+	IMAGE=$BASE_IMAGE:$UID-$GID
 	test ! -z $(docker images -q "$IMAGE") || build_user_image
 	CONTAINER_USER_HOME="/home/$USER"
 fi