npm link can be used to link a local Node.js project into another project just like a normal dependency. npm link sort of emulates running cd my-lib && npm publish && cd ../my-app && npm install my-lib. This is super useful when you're developing two projects in tandem, and usually does mostly the right thing,
The problem is that npm publish potentially prunes a lot of stuff that npm link does not. npm link simply provides a portal (symlink) to the full root of the development copy: a simple single wholesale ln -s ..., which ignores any local .npmignore and the global and implied npm ignores.
npm-reallink is a hack of a script that recursively symlinks the files from my-lib into your global node_modules directory, except for the files that would be ignored if you npm publish'ed my-lib. I use it for TypeScript development, because the TypeScript compiler will use %.ts files in normally-npm link'ed projects, even if a %.js and %.d.ts pair is present, which is liable to break if your consumer project does not specify the same TypeScript configuration (in tsconfig.json) as the library project.
npm-reallink only replaces the local → global npm link (without arguments) call. After calling npm-reallink from within your my-lib/ project root, use plain npm link my-lib from the other project that depends on my-lib, as you would normally.
Copyright 2016 Christopher Brown. MIT Licensed.