The Yarn team is brewing up a new way to resolve dependencies:

this RFC a new alternative and entirely optional way to resolve dependencies installed on the disk, in order to solve issues caused by the incomplete knowledge Node has regarding the dependency tree. We also detail the actual implementation we went with, describing the rational behind the design choice we made.

Pretty exciting if/when they pull it off. The wins:

• Installs ran using Plug’n’Play are up to 70% faster than regular ones (sample app)
• Starting from this PR, Yarn will now be on the path to make yarn install a no-op on CI
• Yarn will now be able to tell you precisely when you forgot to list packages in your dependencies
• Your applications will boot faster through a hybrid approach of static resolutions

Yarn and npm was discussed in-depth on JS Party #29. Spencer writes on the Mixmax blog:

We tested that this flow with npm 6 would work for our needs and we suggest you do too. If you need the absolute fastest package manager, then you may still find Yarn to be best. But if you’re looking to simplify your setup, we’ve found that npm 6 recaptures a critical balance between speed and reliability.

Spencer and team also shared deyarn a command-line tool for converting your projects from Yarn to npm.