anchor.diff:      linux-headers \
       libtool \
       build-base \
  -    pcre-dev \
  +#    pcre-dev \
       zlib-dev \
       wget \
       gnupg \
  
positive.code: #        
  # Philip Hazel's public GPG key for pcre (https://www.pcre.org/). 
      && gpg --keyserver keys.internet-sicherheit.de --recv-key \
          45F68D54BBE23FB3039B46E59766E084FB0F43D8
  
  ### Source download, verify and extract
  RUN wget $NGINX_SOURCE$NGINX_VERSION.tar.gz -O /tmp/$NGINX_VERSION.tar.gz \
      && wget $NGINX_SOURCE$NGINX_VERSION.tar.gz.asc -O /tmp/$NGINX_VERSION.tar.gz.asc \
      && gpg --verify /tmp/$NGINX_VERSION.tar.gz.asc \
      && mkdir -p /usr/src \
      && tar xzf /tmp/$NGINX_VERSION.tar.gz -C /usr/src
  
  ### Source download, verify and extract
  RUN wget $OPENSSL_SOURCE$OPENSSL_VERSION.tar.gz -O /tmp/$OPENSSL_VERSION.tar.gz \
      && wget $OPENSSL_SOURCE$OPENSSL_VERSION.tar.gz.asc -O /tmp/$OPENSSL_VERSION.tar.gz.asc \
      && gpg --verify /tmp/$OPENSSL_VERSION.tar.gz.asc \
      && mkdir -p /usr/src \
      && tar xzf /tmp/$OPENSSL_VERSION.tar.gz -C /usr/src
  
  ### Source download, verify and extract
  RUN wget $PCRE_SOURCE$PCRE_VERSION.tar.gz -O /tmp/$PCRE_VERSION.tar.gz \
      && wget $PCRE_SOURCE$PCRE_VERSION.tar.gz.sig -O /tmp/$PCRE_VERSION.tar.gz.asc \
      && gpg --verify /tmp/$PCRE_VERSION.tar.gz.asc \
      && mkdir -p /usr/src \
      && tar xzf /tmp/$PCRE_VERSION.tar.gz -C /usr/src
  
  ### nginx installation
  RUN cd /usr/src/$NGINX_VERSION \
      && ./configure \
      --with-cc-opt="-O3 -fPIE -fstack-protector-strong" \
      --prefix=/nginx \
  
negative.code:     libc-dev \
      make \
      pkgconf \
  #    curl-dev \
      ca-certificates \  
      # additional build packages              
  #    freetype-dev \
  #    openldap-dev \
  #    gmp-dev \
  #    icu-dev \
  #    postgresql-dev \
  #    libpng-dev \
  #    libwebp-dev \
  #    gd-dev \
  #    libjpeg-turbo-dev \
  #    libxpm-dev \
  #    libedit-dev \
  #    libxml2-dev \
  #    libressl-dev \
  #    libbz2 \
  #    sqlite-dev \
  #    imap-dev \
      ### runtime packages
      && apk add --no-cache --virtual .run-deps \
      s6 \
      su-exec \
  #    curl \
  #    libedit \
  #    libxml2 \
  #    libressl \
  #    libwebp \
  #    gd \
  #    pcre \
  #    zlib \
  #    freetype \
  #    openldap \
  #    gmp \
  #    bzip2-dev \
  #    icu \
  #    libpq \
  #    c-client \
  #
  # GPG key for nginx (http://nginx.org/en/pgp_keys.html)
      && gpg --keyserver keys.internet-sicherheit.de --recv-key \
          # Andrew Alexeev
          A09CD539B8BB8CBE96E82BDFABD4D3B3F5806B4D \
          # Igor Sysoev
  