anchor.diff:  COPY --from=builder /usr/local /usr/local
   COPY --from=builder /opt/conda /opt/conda
   
  -RUN pip --no-cache-dir install ipython Pillow healpy seaborn
  +RUN conda update --no-deps certifi
  +RUN pip --no-cache-dir install ipython Pillow healpy seaborn ipykernel
   
   WORKDIR /src
   
  
positive.code: # The Tractor
  RUN git clone http://github.com/dstndstn/tractor.git tractor \
      && cd tractor \
      && python3 setup-cython.py --with-ceres install --home /usr/local \
      && make version && cp tractor/version.py /usr/local/lib/python/tractor/ \
      && rm -R $(find . -name "*.o" -o -name "*.so") \
      && (cd && PYTHONPATH=/usr/local/lib/python python3 -c "import tractor; print(tractor.__version__)") \
      && echo 2
  
  # Pip installs -- built from source
  RUN pip --no-cache-dir install photutils
  
negative.code: 
  RUN mkdir /homedir && chmod 777 /homedir
  ENV HOME /homedir
  
  # set prompt and default shell
  SHELL ["/bin/bash", "-c"]
  