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This JavaScript library is enjoying quite the surge of popularity lately, and for good reason. It’s extremely useful and clever!

Polyfill.io reads the User-Agent header of each request and returns polyfills that are suitable for the requesting browser.

Meaning you can write JavaScript using modern features and not worry they won’t work. That’s something Babel is also used for, but I imagine there are circumstances you want to use the modern API’s and not compile them down to older workarounds.

We were asked to add it to the Quick Add area:

So we did!

But just to be honest here, we had a little hesitation in doing so. Nothing against the library of course, but we don’t always want to play favorites with libraries like this. We want to walk the line between being useful and accommodating things users want, and not advocating any one particular way of doing things. So we apologize in advance if we can’t accommodate all requests to put your-library-of-choice in there.

Besides, the type ahead feature is cooler anyway! It supports thousands of libraries available via CDN. Put your-library-of-choice on CDNjs and it’ll show up there.