+ # if we are using master, then we are downloading/caching upstream images
+ # we want to use that built in mechanism to avoid re-downloading every job
+ # so we use a dedicated folder to hold the upstream cache
+ UPSTREAM_CACHE=$HOME/upstream_cache
+ if [ "$BRANCH" == 'master' ]; then
+ mkdir -p ${UPSTREAM_CACHE}
+ RESOURCES=$UPSTREAM_CACHE
+ else
+ RESOURCES="${WORKSPACE}/.build/"
+ fi