MoarVM
A runtime built for the 6model object system
..., and asynchronous sockets, timers, processes, and more, generational, parallel, garbage collection, support for numerous language features, including first class functions, exceptions, continuations, runtime loading of code, big integers and interfacing with native libraries. MoarVM provides very little directly - and that's a good thing. It is not tied to a particular way of doing inheritance, roles, mixins, method resolution, type-checking, and so forth.