Why do you think NPM is "the most unreliable package manager"? I don't use Node, but I thought the general consensus was that it's one of the best out there. I'm genuinely curious.
I've had more issues with npm in the last month than I've had with pip, gem, and apt combined over the last two years. "most unreliable package manager" is an apt descriptor.
source: a number of non-trivial node deploys