anchor.diff:  RUN apt-get update \
   	&& apt-get install -y libicu-dev \
   	&& docker-php-ext-configure intl \
  -	&& docker-php-ext-install intl
  +	&& docker-php-ext-install -j$(nproc) intl
   
   # xml
   RUN apt-get update \
   	&& apt-get install -y \
   	libxml2-dev \
   	libxslt-dev \
  -	&& docker-php-ext-install \
  +	&& docker-php-ext-install -j$(nproc) \
   		dom \
   		xmlrpc \
   		xsl
  
positive.code: RUN apt-get update \
  	&& apt-get install -y libgmp-dev \
  	&& ln -s /usr/include/x86_64-linux-gnu/gmp.h /usr/include/gmp.h \
  	&& docker-php-ext-install \
  		gmp \
  		bcmath
  
  
negative.code: 	&& apt-get install -y \
  	libbz2-dev \
  	zlib1g-dev \
  	&& docker-php-ext-install -j$(nproc) \
  		zip \
  		bz2
  
  