Great work! I've replaced npm with yarn for development because it seems to install packages about 10x faster than npm.
Has npm 5 caught up in speed yet?
My comment on another post about the new release might be interesting for you: https://news.ycombinator.com/item?id=14423133
Short version: It's faster, but not as fast as yarn yet.
Great! I would love to see some benchmarks against Yarn.