anchor.diff:  COPY --from=builder --chown=app:app /usr/local/bundle/ /usr/local/bundle/
   COPY --from=builder --chown=app:app /app /app
   
  -#ENV LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libjemalloc.so.2
  -#ENV RACK_ENV=production
  -#ENV RAILS_ENV=production
  -#ENV RAILS_LOG_TO_STDOUT true
  +ENV RAILS_ENV production
  +
  +ENV RAILS_LOG_TO_STDOUT true
  +
  +ENV LD_PRELOAD=/usr/lib/x86_64-linux-gnu/libjemalloc.so.2
  +
  +# throw errors if Gemfile has been modified since Gemfile.lock
  +RUN bundle config set --global frozen 1
  +
  +# two jobs
  +RUN bundle config set --global jobs 2
  +
  +# install only production gems without development and test
  +RUN bundle config set --global without development test
  +
  +# retry 5 times before fail
  +RUN bundle config set --global retry 5
  +
  +RUN bundle install
  +
  +SHELL ["/bin/bash", "-o", "pipefail", "-c"]
  +
  +EXPOSE 3000/tcp
  +
  +CMD ["rails", "server", "-b", "0.0.0.0"]
  +
   #ENV RAILS_SERVE_STATIC_FILES true
   #
   #WORKDIR /app
  
positive.code: 
  FROM ruby:3.0.2-slim
  
  RUN set -eux; \
      apt-get update -y ; \
      apt-get dist-upgrade -y ; \
  
negative.code:     apt-get clean -y ; \
      rm -rf /var/lib/apt/lists/*
  
  WORKDIR /app
  
  #RUN groupadd --gid 1000 app && \
  #  useradd --uid 1000 --no-log-init --create-home --gid app app
  #USER app
  