anchor.diff:  
   # cleanup
       && service apache2 stop \
  -    && apt-get install -yf libapache2-mod-php5.6 libapache2-mod-php7.0 && a2dismod php5.6 && a2dismod php7.0 && a2dismod php7.1 \
  +    && apt-get install -yf libapache2-mod-php5.6 libapache2-mod-php7.1 && a2dismod php5.6 && a2dismod php7.0 && a2dismod php7.1 \
   
   # fix v8js reference of json first
       && mv /etc/php/5.6/apache2/conf.d/20-json.ini /etc/php/5.6/apache2/conf.d/15-json.ini \
       && mv /etc/php/5.6/cli/conf.d/20-json.ini /etc/php/5.6/cli/conf.d/15-json.ini \
       && mv /etc/php/5.6/cgi/conf.d/20-json.ini /etc/php/5.6/cgi/conf.d/15-json.ini \
   
  -# switch to php7.0 version before any other install
  +# switch to php7.0 version as default
       && update-alternatives --set php /usr/bin/php7.0 \
       && pecl config-set php_ini /etc/php/7.0/cli/php.ini \
       && pecl config-set ext_dir /usr/lib/php/20151012 \
       && pecl config-set bin_dir /usr/bin \
       && pecl config-set php_bin /usr/bin/php7.0 \
       && pecl config-set php_suffix 7.0 \
  +    && apt-get install -yf php7.0-dev \
  +    && a2enmod php7.0 \
   
       && rm -rf /tmp/* \
       && apt-get -yf autoremove \
  
positive.code:     && ln -sf /etc/php/7.1/mods-available/couchbase.ini /etc/php/7.1/cli/conf.d/20-couchbase.ini \
      && ln -sf /etc/php/7.1/mods-available/couchbase.ini /etc/php/7.1/cgi/conf.d/20-couchbase.ini \
  
  
      && a2enmod php7.0 \
  
  # increase memcache max size from 64m to 2g
      && sed -i -e "s/^\-m 64/\-m 2048/g" /etc/memcached.conf \
  
  
negative.code: 
  # install nodejs, memcached, redis-server, openvpn, mongodb, and couchdb
      && apt-get install -yf nodejs memcached php-memcached redis-server openvpn mongodb-org php-mongodb couchdb \
      && ln -sf "$(which nodejs)" /usr/bin/node
  
  # setting up dotnet, awscli, golang, php
  