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README.md

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 lua-mapreduce
 =============
 
-Lua map-reduce implementation based in MongoDB.
+Lua map-reduce implementation based in MongoDB. It differs from
+[ohitjoshi/lua-mapreduce](https://github.com/rohitjoshi/lua-mapreduce)
+in the basis of the communication between the processes. In order to
+allow fault tolerancy, and to reduce the communication protocol
+complexity, this implementation relies on mongoDB. So, all the data
+is stored at auxiliary mongoDB collections.
+
+This software depends in:
+
+- [Lua 5.2](http://www.lua.org/)
+- [pabloromeu/luamongo](https://github.com/pabloromeu/luamongo/), a fork of 
+  [moai/luamongo](https://github.com/moai/luamongo) for Lua 5.2 and with minor
+  improvements.