wish to become mapred developer

[shashank shekhar]

hii.i want to contribute to mapreduce but i now i am in beginner stage so i
have few question for which  i need answer.
first thing which i want to know is about bugs.
Do i need to find bugs myself or the bugs are organised in some kind of list
using which i can know about them and  fix them.
Pls do reply ..thanks