The project provides Result-type similar to Result-type in Rust that allows to return either successfull result or otherwise some kind of error. In Java native way of reporting errors are exceptions, either checked or unchecked, but Result-type provides a way to pass error enformation as a first-class value through the code written in functional style. Routines are provided for interoperability of normal code that uses exception and functional code that uses Result-type, so that exceptions can be catched and propagated as errors in Result-type and then rethrown again later in the control-flow.