to participate as developper

Hi ,
my  name is karim jebalia I am tunisien (north africa) 
I am 26 years old I have worked for 3 years in developping application
for banking and financial company
now I am in Germany (munchen) I work with a company developping J2EE
application in the domaine of B2B
I have used in my work life a lot of open source sofware (I am still
using a lot of open source tools )and I am decided to contribute as
wel as I can to open source community
I want to knew how to join an open source project as developper or
tester or in a several part of a project

thanks and best regards 
karim jebalia 
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