[kozyraki]

My view on this the following: Mesos is similar to the kernel of a conventional operating system (e.g. Linux). It provides very basic services (scheduling, interrupts, device management, etc) and a syscall API. But nobody wants to program to this API. Hence you need libc or other similar libraries to provide a higher level API that programmers use to interact with the kernel. Kubernetes, Marathon, Aurora, etc are such libraries, each optimizing for a different class of applications and providing different functionality. The two (the kernel and the libraries) need each other.

[boulos]

I see what you're saying Christos, but I think I'd prefer "runtime" over library (library sounds like it's just a little convenience).

[kozyraki]

Sure, pthreads and other thread libraries that include a lot of runtime functionality would probably be a better analogy.