anchor.diff:      && apt-get -y autoclean
   
   # Install rbenv
  -RUN git clone --depth=1 https://github.com/rbenv/rbenv.git /root/.rbenv \
  -    && cd /root/.rbenv \
  +ENV RBENV_ROOT=/root/.rbenv
  +RUN git clone --depth=1 https://github.com/rbenv/rbenv.git $RBENV_ROOT \
  +    && cd $RBENV_ROOT \
       && src/configure \
       && make -C src
  -ENV PATH /root/.rbenv/shims:/root/.rbenv/bin:$PATH
  +ENV PATH $RBENV_ROOT/shims:$RBENV_ROOT/bin:$PATH
   RUN echo 'eval "$(rbenv init -)"' >> /etc/profile
   RUN echo 'eval "$(rbenv init -)"' >> .bashrc
   RUN mkdir -p "$(rbenv root)"/plugins \
  
positive.code:     && rbenv global ${DEFAULT_RUBY_VERSION}
  
  # Install pyenv
  RUN git clone --depth=1 https://github.com/pyenv/pyenv.git ~/.pyenv \
      && cd /root/.pyenv \
      && src/configure \
      && make -C src
  ENV PATH /root/.pyenv/shims:/root/.pyenv/bin:$PATH
  RUN echo 'export PYENV_ROOT="$HOME/.pyenv"' >> .bashrc
  RUN echo 'export PATH="$PYENV_ROOT/bin:$PATH"' >> .bashrc
  RUN echo 'eval "$(pyenv init -)"' >> ~/.bashrc
  
negative.code: ENTRYPOINT /bin/bash
  
  ENV RUBY_VERSIONS="2.5.8 2.6.6 2.7.2 3.0.0" \
      OLDEST_RUBY_VERSION=2.5.8 \
      NEWEST_RUBY_VERSION=3.0.0 \
      DEFAULT_RUBY_VERSION=2.6.6 \
      BUNDLER1_VERSION=1.17.3 \
      BUNDLER2_VERSION=2.2.11 \
  