I had checked the repo it very big for a new commers to under stand. I have made some contrubution in SasanLabs · GitHub which was understandable. But how should i start contributing to big repos like Jenkins. (I am new to Open Source).
Adoping a Jenkins plugin might be a good idea? Jenkins plugins have much smaller source trees than, for example, the Jenkins core. Besides, the initial taska would, most likely, be of a more administrative nature.
Adopting a plugin makes only sense when you’re using the plugin yourself and the plugin has open issues that you want to fix or you have ideas for new features that benefit the users of the plugin.
Start with Contribute code
If you want to understand Jenkins look at My Jenkins Learning Notes – Understanding the Architecture