In this way, previous standar cmake installation will not work?

It is good to have cereb-nest pip-installable, but it should be retro-compatible (e.g., with the collabs that install cerebnest from source.

Standard CMake installation still works, maybe with some adaptations to the instructions with regards to the directory instructions like cd. I wanted to leave the source installation instructions there but it seems I removed them. I'll change this when I have time and finally test the importance of the nest_bin_vars.sh

In this way, previous standar cmake installation will not work?

It is good to have cereb-nest pip-installable, but it should be retro-compatible (e.g., with the collabs that install cerebnest from source.

Aaaaah no I see what you mean, you should always freeze your dependencies in notebooks and other "deployments":

• Install specific versions
• Clone specific commits

Otherwise when any of your dependencies change your notebook breaks. Is there anything that you know of for SGA2 review that depends on this? If so we will wait until it's passed to change this. You could also go to these deployments and just appends a commit SHA to the clone command.

I would not let BSP notebooks to break even after SGA2 review..they could still be used for educational purposes, dissemination etc..If at all, we could make them compatible to the new cerebnest when they also adapt them to the new eBRAINS platform.

Ok, if they need to function in perpetuity the dependencies need to be frozen, there's no way around that.

After tons of messing with Travis and NEST I think I've got to an agreeable situation:

• pip runs the CMake install
• aborts if the NEST_MODULE_PATH and SLI_PATH aren't properly set (injecting code into .bashrc felt a bit virus-y) and gives a nice error message on how to do it:

    Exception: Please make sure the following env vars contain these directories:
    * NEST_MODULE_PATH: '/home/travis/nest-2.18.0/lib/nest'
    * SLI_PATH: '/home/travis/nest-2.18.0/share/sli'
    You can do so by making sure the following 2 commands are executed on startup (eg. placed in ~/.bashrc):
    export NEST_MODULE_PATH=/home/travis/nest-2.18.0/lib/nest:$NEST_MODULE_PATH
    export SLI_PATH=/home/travis/nest-2.18.0/share/sli:$SLI_PATH

All that's left to do now is to reattach the CMake install instructions to the README

@alberto-antonietti @AliceGem could you take another look to see if you like the PR now? Could you also test the pip package with pip install cereb-nest and the CMake install with the new instructions? I'm not on Linux atm

@AliceGem maybe update the information in setup.py? The description etc.