A Component Object Model defines a framework for creating objects and calling their methods independently of object location. This allows distributing objects used by one process among multiple executables or multiple computers. There are numerous COM implementations currently in use, such as the classic CORBA, Microsoft's DCOM upon which Windows is built, and, to some degree, DBUS, ubiqutous on Linux due to its use by systemd.

Casycom is one such COM framework, providing object creation and lifetime management, fully asynchronous messaging and event loop, and transparent access to out-of-process objects. It is very lightweight, a static library compiled to only 20k, and at only 3k lines of code, it is easy to fully review and understand.