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@@ -221,6 +221,8 @@ There're also some great commercial libraries, like [amchart](http://www.amchart
 
 * [mori](http://swannodette.github.io/mori/) - A library for using ClojureScript's persistent data structures and supporting API from the comfort of vanilla JavaScript.
 * [buckets](https://github.com/mauriciosantos/buckets) - A complete, fully tested and documented data structure library written in JavaScript.
+* [immutable-js](https://github.com/facebook/immutable-js) - Immutable Data Collections including Sequence, Range, Repeat, Map, OrderedMap, Set and a sparse Vector.
+
 
 ## Date
 *Date Libraries.*