Why I'm Working on Yarn https://yehudakatz.com/2016/10/11/im-excited-to-work-on-yarn-the-new-js-package-manager-2/ (argues, rightly IMO, on the importance of community design over implementation details)
miniblog.
Related Posts
The future of Yarn: https://github.com/yarnpkg/yarn/issues/6953
Breaking up into libraries to enable reuse, and porting to Typescript!
A nice example of the remarkable modularity in the npm ecosystem: Yarn just split out its lockfile parser https://github.com/yarnpkg/yarn/pull/4114
This is nifty: yarn will resolve conflicts in lockfiles automatically! https://github.com/yarnpkg/yarn/pull/3544 (novel? I haven't seen other tools do this)