anchor.diff:  
   COPY ./requirements.txt ${KPI_SRC_DIR}/
   # Only install if the current version of `requirements.txt` differs from the one used in the base image.
  -RUN diff -q "${KPI_SRC_DIR}/requirements.txt" /srv/tmp/base_requirements.txt || \
  +RUN if [ "$(diff -q ${KPI_SRC_DIR}/requirements.txt /srv/tmp/base_requirements.txt)" ]; then \
       pip-sync "${KPI_SRC_DIR}/requirements.txt" \
  -    || true # Prevent non-zero exit code.
  +    ; fi
   
   
   ##########################################
  
positive.code: 
  COPY ./package.json ${KPI_SRC_DIR}/
  # Only install if the current version of `package.json` differs from the one used in the base image.
  RUN diff -q "${KPI_SRC_DIR}/package.json" /srv/tmp/base_package.json || \
      npm install \
      || true # Prevent non-zero exit code.
  
  
  ##########################################
  
negative.code: 
  COPY ./apt_requirements.txt ${KPI_SRC_DIR}/
  # Only install if the current version of `apt_requirements.txt` differs from the one used in the base image.
  RUN if [ "$(diff -q ${KPI_SRC_DIR}/apt_requirements.txt /srv/tmp/base_apt_requirements.txt)" ]; then \
          apt-get update && \
          apt-get install -y $(cat ${KPI_SRC_DIR}/apt_requirements.txt) && \
          apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* \ 
      ; fi
  
  
  ###########################
  