At Codeception we are glad to receive contributions and patches from the community. There are a few guidelines that we need contributors to follow so that we can have a chance of keeping on top of things.
Please check the guide for sending your contributions with Github at https://github.com/Codeception/Codeception/wiki/Git-workflow-for-Codeception-contributors
All contributions must follow the coding standards described at: https://github.com/Codeception/Codeception/wiki/Codeception-coding-style-standard
If you want to contribute documentation you are asked to send your changes to the /docs/ folder: https://github.com/Codeception/Codeception/tree/master/docs. This files are the source for the codeception website guides: http://codeception.com/docs/01-Introduction. Remind to send your documentation improvements to the right "repository branch" depending on the Codeception version you are working with: 2.0, master,...