anchor.diff: -FROM cyberdojo/user-base
  +FROM alpine:3.4
   MAINTAINER Jon Jagger <jon@jaggersoft.com>
   
   # - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  -# 1. install tini (for pid 1 zombie reaping)
  -# https://github.com/krallin/tini
  -# https://blog.phusion.nl/2015/01/20/docker-and-the-pid-1-zombie-reaping-problem/
  -
  -USER root
  -RUN apk add --update --repository http://dl-cdn.alpinelinux.org/alpine/edge/community/ tini
  -ENTRYPOINT ["/sbin/tini", "--"]
  -
  -# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  -# 2. install docker-client
  +# 1. install docker-client
   # Launching a docker app (that itself uses docker) is
   # different on different host OS's... eg
   #
  
positive.code:   && apk del curl
  
  # - - - - - - - - - - - - - - - - - - - - - -
  # 5. install ruby and json gem
  
  USER root
  RUN  apk update && apk add ruby ruby-irb ruby-io-console ruby-bigdecimal tzdata bash
  RUN  gem install json_pure --no-ri --no-rdoc
  
  # - - - - - - - - - - - - - - - - - - - - - -
  # 6. install commander
  
  RUN  mkdir /app
  COPY cyber-dojo.sh          /app
  
negative.code: COPY start_point_check.rb   /app
  COPY start_point_inspect.rb /app
  COPY start_point_pull.rb    /app
  WORKDIR /app
  
  
  