[hansgru]

> I don't understand the local vs global dependency thing. What does NPM do differently from Maven?

As others have pointed out, NPM as a default is using "local" dependencies, (something I couldn't achieve with Maven easily).

"Local" means that the dependencies are in a sub-directory of the project, and that the transient dependencies are in sub-sub-directories too if needed.

With NPM, for us some of the implications of this are the following:

- being "self contained" I can check in a VCS and tag it "completely" or just zip it and send somewhere else, where it can be built "as it is", even on CI machines or production machines that have no Internet connection, nor do require a company internal Maven server.

- bugs and issues with building are reproducible. The "it builds on my machine" doesn't happen anymore. (Just search the different Apache mailing lists of how often this happened even in those open source projects). We had this problem very very often - to the point where several projects were migrated to ANT again.

- the availability of public Maven Repos, their mirrors and their sync is just bad (sometimes it's the corporate firewall/proxy the problem), so builds just fail all to often. Many companies don't use internal Maven Repo Mirror

- none where I worked had one, nor could we convince the management to finance one.

- very often (even visible in open source projects that build with Maven), there are some dependencies (maybe not from the start of the project, or maybe only temporarily) that are not available in the official repos, so need to be manually added. Doing this in a sub-directory is much easier, and it needs to be done only once, so others will just use it.

These are just a few issues that NPM seems to have been solved nicely (or just not having them because of of the "local" defaults).

Of course, there are also disadvantages of this "local" approach (like the redundant disk space usage - where the global one is very efficient), but from my experience all these disadvantages pale compared to the problems and frustration Maven brought in many projects that adopted it.