# PouchDB 2.2.0

By: Dale Harvey
Published: 01 May 2014

PouchDB 2.2.0 is now released! Please file issues or tell us what you think. We would also like to give a huge thanks to our new and existing contributors.

We have removed the ES5 shims from PouchDB. If you require support for older browsers, it can be included from https://github.com/es-shims/es5-shim.

### Major Changes:

- Fix replication for large databases (#1954)
- Persistent map/reduce (#1658)
- Fix experimental `.sync()` API (#1696)
- `.replication()` API switched to an `EventEmitter` (#1916)
- `.changes()` API switched to an `EventEmitter` (#1768)
- Experimental LevelDB-based LocalStorage adapter (#44)
- Performance improvements (#1869, #1871, #1889, #1897, #1990)
- Remove ES5 shims (#1753)
- Performance tests (#113)

###### Complete list of changes