As of PouchDB commit f17d58, this project is deprecated. PouchDB now has a custom extend() function that is inside of PouchDB itself.

You can still use this repo and that's fine, but it's not a requirement for using PouchDB or writing PouchDB plugins. Feel free to use whatever extend() you like!

Original docs follow.

extend() method taken from JQuery 1.9.0 for use in PouchDB

We use this because other extend libraries have been shown to not play nicely with Ember.js and IndexedDB (see pouchdb/pouchdb#2158).