anchor.diff:          php7-iconv \
           php7-mbstring \
           php7-curl \
  +        php7-ctype \
           php7-opcache \
           php7-sockets \
           php7-openssl
  
positive.code:         php7-tokenizer
  
  RUN composer install --no-dev --no-scripts --no-suggest --optimize-autoloader \
   && composer require "daverandom/libdns:^2.0" --no-scripts --no-suggest --optimize-autoloader
  
  COPY ./src /srv/src
  COPY ./res /srv/res
  
negative.code: 
  # =============================
  
  FROM alpine:3.8
  
  WORKDIR /srv
  
  