Link A JavaScript Package Locally

If you are putting together a JavaScript package and you'd like to test it out locally before putting it on NPM, use npm link.

First, from the directory of the package you are creating run:

$ npm link

This will symlink the package to the global node modules directory.

Then, from the base project directory that you want to try importing and using the package from, run:

$ npm link name-of-package

This will create an additional symlink from the global node modules directory to the node_modules of this target project.

You'll now have access to the project, try an import to get what you need and try it out.

See man npm-link for more details.