IMAGE build
LAYER shared/alpine

RUN EOF
    # Add edge/testing repository
    echo '@em http://dl-cdn.alpinelinux.org/alpine/edge/main' >>/etc/apk/repositories
    echo '@et http://dl-cdn.alpinelinux.org/alpine/edge/testing' >>/etc/apk/repositories
    echo '@ec http://dl-cdn.alpinelinux.org/alpine/edge/community' >>/etc/apk/repositories

    # Install s6 supervisor
    apk --no-cache add s6@em
EOF