anchor.diff:  RUN julia -e 'Pkg.add("IJulia"); using IJulia'
   
   # registers global kernel
  -RUN cp -r ~/.local/share/jupyter/kernels/julia-0.4 /usr/local/share/jupyter/kernels
  +RUN cp -r ~/.local/share/jupyter/kernels/julia-$JULIA_VER_MAJ /usr/local/share/jupyter/kernels
   
   # rewrite julia's kernel configuration
  -ADD julia-kernel.json /usr/local/share/jupyter/kernels/julia-0.4/kernel.json
  +ADD julia-kernel.json /usr/local/share/jupyter/kernels/julia-$JULIA_VER_MAJ/kernel.json
   
   # R
   # http://irkernel.github.io/installation/
  
positive.code: RUN cd ~/llvm_build \
  	&& make ENABLE_OPTIMIZED=1 DISABLE_ASSERTIONS=1 -j"$(nproc --all)" \
  	&& make -j"$(nproc --all)" install \
  	&& ln -s /usr/local/lib/libLLVM-3.7.1.so /usr/local/lib/libLLVM.so \
  	&& ldconfig \
  	&& cd .. && rm -rf llvm_build && rm -rf llvm
  
  # node
  RUN wget https://github.com/nodejs/node/archive/v6.3.1.tar.gz \
  	&& tar xf v6.3.1.tar.gz && cd node-6.3.1 \
  	&& ./configure \
  	&& make -j"$(nproc --all)" \
  	&& make -j"$(nproc --all)" install \
  	&& cd .. && rm -f v6.3.1.tar.gz && rm -rf node-6.3.1
  
  # reinstall npm with the lastest version
  RUN npm cache clean \
  
negative.code: 
  # llvm needs CMake 2.8.12.2 or higher
  # https://cmake.org/download/
  ENV CMAKE_VER_MAJ 3.6
  ENV CMAKE_VER_MIN .1
  ENV CMAKE_VER $CMAKE_VER_MAJ$CMAKE_VER_MIN
  
  RUN wget https://cmake.org/files/v$CMAKE_VER_MAJ/cmake-$CMAKE_VER.tar.gz \
  	&& tar xf cmake-$CMAKE_VER.tar.gz && cd cmake-$CMAKE_VER \
  	&& ./bootstrap && make -j"$(nproc --all)" && make -j"$(nproc --all)" install \
  	&& cd .. && rm -rf cmake-$CMAKE_VER && rm -f cmake-$CMAKE_VER.tar.gz \
  	&& echo "export CMAKE_ROOT=/usr/local/share/cmake-$CMAKE_VER_MAJ" > /etc/profile.d/cmake-root.sh \
  	&& source /etc/profile
  
  # Python 2
  # https://github.com/h2oai/h2o-2/wiki/Installing-python-2.7-on-centos-6.3.-Follow-this-sequence-exactly-for-centos-machine-only
  ENV PYTHON2_VER_MAJ 2.7
  ENV PYTHON2_VER_MIN .11
  ENV PYTHON2_VER $PYTHON2_VER_MAJ$PYTHON2_VER_MIN
  
  RUN wget https://www.python.org/ftp/python/$PYTHON2_VER/Python-$PYTHON2_VER.tar.xz \
  	&& tar xf Python-$PYTHON2_VER.tar.xz \
  	&& cd Python-$PYTHON2_VER \
  	&& ./configure --prefix=/usr/local/python$PYTHON2_VER_MAJ --enable-shared --with-cxx-main=/usr/bin/g++ \
  	&& make -j"$(nproc --all)" \
  	&& make -j"$(nproc --all)" altinstall \
  	&& echo "/usr/local/lib" > /etc/ld.so.conf.d/usrLocalLib.conf \
  	&& ldconfig \
  	&& cd .. && rm -f Python-$PYTHON2_VER.tar.xz && rm -rf Python-$PYTHON2_VER
  
  # pip for Python 2
  RUN curl -O https://bootstrap.pypa.io/get-pip.py \
  	&& /usr/local/python$PYTHON2_VER_MAJ/bin/python$PYTHON2_VER_MAJ get-pip.py \
  	&& rm -f get-pip.py
  
  # Python 3
  ENV PYTHON3_VER_MAJ 3.5
  ENV PYTHON3_VER_MIN .1
  ENV PYTHON3_VER $PYTHON3_VER_MAJ$PYTHON3_VER_MIN
  
  RUN wget https://www.python.org/ftp/python/$PYTHON3_VER/Python-$PYTHON3_VER.tar.xz \
  	&& tar xf Python-$PYTHON3_VER.tar.xz && cd Python-$PYTHON3_VER \
  	&& ./configure --prefix=/usr/local --enable-shared --with-cxx-main=/usr/bin/g++ \
  	&& echo "zlib zlibmodule.c -I\$(prefix)/include -L\$(exec_prefix)/lib -lz" >> ./Modules/Setup \
  	&& make -j"$(nproc --all)" \
  	&& make -j"$(nproc --all)" altinstall \
  	&& ln -s /usr/local/bin/python$PYTHON3_VER_MAJ /usr/local/bin/python3 \
  	&& ln -s /usr/local/bin/pip$PYTHON3_VER_MAJ /usr/local/bin/pip3 \
  	&& ldconfig \
  	&& cd .. && rm -f Python-$PYTHON3_VER.tar.xz && rm -rf Python-$PYTHON3_VER
  
  # Upgrade pip
  # https://pip.pypa.io/en/stable/installing/#upgrading-pip
  