More specifically I wrote a full REST API to be used by the mobile applications. It includes a flexible routing system, automatic input escaping, output filtering, middleware procedures, controllers, resolvers and repositories for each endpoint.
I also wrote the custom online payment gateway for stripe with that includes local caching, transparent API calls and helper classes.
The main object-relational mapping system is also my implementation. It consists of an eloquent inspired query builder and abstract model with relations, pivoting, magic getters and caching for each dataset. The system also includes a collection implementation that helps with grouping, parallel procedures and filtering.
Lastly I am always busy with code reviews and smaller features and bug
introducing fixing ;)