We are super happy to get people interested in contributing and advancing HTML5 gaming in general. Also we are very open to communication so anything you have in mind you are pleased to just contact us and ask away. In any case we welcome you warmily to contribute to the project.
You can contact FlaTWorld the best by sending us message through gitter: https://gitter.im/Hachitus/FlaTWorld or through e-mail: japetus@saunalahti.fi.
We recommend to debug and fix any bugs you find first and then send us a pull request. The same applies to new features. We can always finish and fine-tune new features together, but if you at least start and do some ground work it will surely speed it up. If there are any questions regarding the solutions you might end up with in the pull request or the internal working of the engine, you are free to just throw us a message!
If you are unable to fix the bug or create the feature by yourself, please setup a detailed explanation of the issue (or feature) and how to recreate it in FlaTWorld issues.
Keep in mind that we use YUIDoc for documenting so follow the documentation way that has been used throughout the code. Everything should be documented, but if you are in a hurry and only document it very lightly, please add @todo-mark to the sections you think would need more documentation!
We use jshint and jscs to write clean code. You must use the configurations found at the root of the FlaTWorld project (.jshint and.jscs). For example with sublime you can set them up easily with sublimelinter.
We have cross platform engine, which should be supported in most devices and environments. This mean touch should work without problem and all the major browsers. You might not have tools to test this yourself, but we have browserstack sponsoring us their testing platform, that enables us to do that. So please try to test the features and bugs as thoroughly as you can and after that submit it to us for testing.