I'm developing microservice architecture on nodejs. I moved 'core' functionality to separate git repository, and each 'service' add that core as npm dependency.
In service I use core as

require('core/module1');

In that case nodejs takes 'core' from node_modules, it's ok for production but for development I want to take 'core' from the external folder not from node_modules.
My main idea - do changes in 'core' and immidiately get the result in 'service'.
I cannot use NODE_PATH for specify external 'core' folder, because I've used it now.
I found solution to use 'app-module-path' module for adding additional directories to the Node.js module search path.

if(isDevelopment()){
    require('app-module-path').addPath('path_to_core_folder');
}

It's working solution, but maybe you can suggest some more clear way?
My folders structure

- core
    module1

- service1
    -index.js
    -node_modules
      -core

Thanks.