A quick view on WordPress, Mantis and Jenkins plug-in API

I’m preparing a plug-in API proposal for TestLink, and thought that the best way to learn how to write a good plug-in API would be by looking at other application’s plug-in API’s. This post contains information that I gathered for creating this new API, but that may also be useful for other programmers. I used WordPress, Mantis and Jenkins in this study. Let me know if you find any mistakes or if you have any other suggestions.