This project is a new runtime for active-object type languages. It is being built to be efficient and as a test-bed for new ideas. In particular we target a light version of the SCOOP language, and provide a compiler for this language.

The runtime is written in C and uses a few external libraries, most notably

• libffi (to encapsulate calls)
• TBB (just the concurrent queues)
• ConcurrencyKit (again, just for the queues)

I often shorten the name of the project to qs to symbolize the central role that concurrent queues have in the runtime. The runtime focuses on the concurrent aspects of active-objects and does not (yet) include a garbage collector.

The runtime is basically a lightweight thread implementation, a scheduler, and a communication system built on the concurrent queues.

The compiler is written in Haskell and is relatively small (about 4700 lines). It uses LLVM as a compilation target and to do the lower level optimizations. It generates code that calls the runtime, and many tests/benchmarks are contained in the tests directory. It also includes a very minimal base library that grows as needed.