I work on a game that I plan on releasing on GameJolt (it's a site that hosts indie games). It has a very nice achievement system, scoreboards and cloud storage. In the process I created a script that can be used to communicate with the GameJolt API that I've turned into a plugin and decided to share with the community.
It has most of the API but still lacks features so it's still WIP and will be improved. Hope someone finds it useful.