Integrating Cucumber/Ruby with bamboo

[Santosh Negi]

I am new to ruby & bamboo. I'm using Cucumber with Ruby and wants to integrate it with bamboo. Can anyone help with 
1. how to write RakeTask
2. how to write script which will call RakeTask in bamboo
As of now when build is kicked off in bamboo, its doing the checkout of source code to a folder. After that getting error in the logs.
Note: I am running simple cucumber tests, which are workign fine in my local system.