anchor.diff:      /src/legacypipe/py/{legacypipe,legacyzpts}
   
   # update legacypipe
  -RUN cd /src/legacypipe && git pull && git checkout preburn-lslga && git describe && echo 1 && \
  +RUN cd /src/legacypipe && git pull && git describe && \
     python    -m compileall /src/legacypipe/py/{legacypipe,legacyzpts} && \
     python -O -m compileall /src/legacypipe/py/{legacypipe,legacyzpts}
   
  
positive.code:     conda install python=3.7 pip numpy scipy && \
      conda clean -a -y
  
  # Pip installs -- binary
  RUN for x in \
      setuptools \
      wheel \
      psycopg2-binary \
      matplotlib \
      astropy \
      zmq \
      cython \
      ; do pip --no-cache-dir install $x; done
  
  # ugly: Tractor's mp_fourier module detects the $CC='icc' exactly
  # These are in /opt/intel/bin, which is on the PATH.
  ENV CC icc
  
negative.code:     && make clean \
      && (cd && PYTHONPATH=/usr/local/lib/python python3 -c "import astrometry; print(astrometry.__version__)")
  
  # Pip installs -- binary.  We need cython for the tractor.
  RUN for x in \
      setuptools \
      wheel \
      psycopg2-binary \
      matplotlib \
      astropy \
      zmq \
      cython \
      ; do pip --no-cache-dir install $x; done
  
  # The Tractor
  RUN git clone http://github.com/dstndstn/tractor.git tractor \
      && cd tractor \
  