It uses a very different dependency resolution algorithm, the biggest difference as I understand it is it will install dependencies maximally flat whereas npm 2

It uses a very different dependency resolution algorithm, the biggest difference as I understand it is it will install dependencies maximally flat whereas npm 2 was much more nested. I believe the reason it is slower is it can't do as much parallelism as npm 2. Also, npm 2 was susceptible to a lot of race conditions and non-determinism, especially with compiled dependencies.