Everything You Wanted to Know About Yarn Package Manager (opens in new tab)

http://yehudakatz.com/2016/10/11/im-excited-to-work-on-yarn-... for those who where curious.

Well, most people don't want to know much about Yarn. Granted, mostly because they don't even know it exists :)

What do you expect when Yarn has been out for less than a couple of weeks and this person isn't involved with the project in any way?

I was thinking the same thing. I want to know about the pitfalls and reasons not to use yarn. For example, does it support modules from github?

What can be learnt from lein? (I've not used Clojure enough to know.)

I would also like to hear more about this!

Because you can only specify exact versions for your top-level dependencies. Whether or not they pin versions of their own dependencies is up to their own maintainers; you can't control it from package.json. And, while a lot of npm packages adhere to semver and avoid shipping breaking changes on minor version number bumps, a lot of npm packages don't. So you can get hosed through no fault of your own by an Nth-level dependency.

'npm shrinkwrap' solves this by pinning the currently installed versions of everything under node_modules/, regardless of dependency depth. Yarn does the same thing, but by default rather than, as with npm, an optional extra. There's an argument to be made that the correct place to shrinkwrap, if you want to, is in your build process. But I suspect that, in practice, Yarn defaulting to it will prove a net positive, albeit a bit of a speedbump for people looking to do turnkey migrations from npm.

I don't get why people say this. You're acting like the npm team is desperate for contributions and fixes and the Yarn people are like "No! We'll make our OWN tool!".

It's the literal opposite. npm hasn't been open to contributions or fixes for years.

A lot of people say this and I'll repeat the answer: go look at npm's source code and tell me you'd like to "patch in" a large change such as the one Yarn takes on.

No seriously, go look at their source code. In particular go look at the caching code, one of the big things that Yarn fixes. You think their time would have been better spent hacking on that?

My favorite thing about the post* that introduced Yarn, itself a rewrite of a basic component, is that the author(s) unironically began with "In the JavaScript community, engineers share hundreds of thousands of pieces of code so we can avoid rewriting basic components, libraries, or frameworks of our own."

*https://code.facebook.com/posts/1840075619545360?_fb_noscrip...