Store npm packages offline without having to install them every time

Question

I've got a lot of node.js projects and I keep creating new ones every now and then.

They all use mostly the same packages and versions. But for each project the npm install re-builds the whole package (thankfully doesn't download as well because it stores it in cache). But still, building every package from cache takes a lot of time when it could just store the built packages in a separate cache and use those instead.

Is there something that does exactly that?

I'm guessing there must be something because lot of PAAS servers like OpenShift and even fiddles like runnable.com does this very efficiently.

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Edit: digging around a bit found following info, might be useful:

• https://stackoverflow.com/questions/11677798/can-i-use-heroku-buildpacks-to-deploy-to-my-own-local-server

• https://stackoverflow.com/questions/12607209/is-there-a-working-nodejs-phantomjs-heroku-buildpack

• http://mattstauffer.co/blog/laravel-on-heroku-using-a-buildpack-locally-to-mimic-your-heroku-environment-nginx