y2 - An experiment in using Yarn 2 with Yarn 1 defaults

Building off some of my notes in yarn-vs-npm, I wondered out loud what a version of Yarn 2 looks like where it's deployed like a normal npm package, and has defaults which align with traditional node projects.

This is the result of that. It's a fork of berry (here) forked from 2da8101 which defaults to the loosest resolution mode, and uses node_modules.

Usage:

npm install -g y2

mkdir y2k
cd y2k

y2 init
y2 add --dev typescript
y2 tsc

tree . -L 1
.
├── README.md
├── node_modules
├── package.json
└── yarn.lock

Note

Alternative take: You can use yarn set version berry && yarn config set nodeLinker node-modules to have the yarn command default to v2, and node_modules are default too. Thanks @merceyz! This will allow you to still have yarn 1 behavior in existing yarn 1 projects, but any new project gets the same experience as above.

Building

Get a CLI build created in berry, then copy it into the vendor folder.

cd berry
yarn build:cli

cd ..
cp berry/packages/yarnpkg-cli/bundles/yarn.js vendor

Prod

Be careful with this, it's definitely safe to say y2 is not battle tested. My specific changes:

• I switched nodeLinker to "node_modules" and pnpMode to "loose" by default, this means you will just get a yarn.lock and node_modules
• I switched all package names from @yarnpkg/x to @orta/yarn- (this probably does not matter, because y2 runs with a bundled copy of yarn.js)
• I removed the default patches which are normally applied to fsevents, resolve & typescript ( I believe these only exist for PNP support )
• I turned off the telemetry

License

What little code in here I made it MIT. The vendored copy of Yarn 2 is BSD 2-Clause.

Note

Worth stressing, this isn't a "Yarn 2 sucks" project. I'd like to use Yarn 2, this allows me to give it a shot at using it as my primary dependency manager for a while.