Concurrency by default: using permissions to express dataflow in stateful programs

The rise of the multicore era is catapulting concurrency into mainstream programming. Current programming paradigms build in sequentiality, and as a result, concurrency support in those languages forces programmers into low-level reasoning about execution order. In this paper, we introduce a new programming paradigm in which concurrency is the default. Our Aeminium language uses access permissions to express logical dependencies in the code at a higher level of abstraction than sequential order. Therefore compiler/runtime-system can leverage that dependency information to allow concurrent execution. Because in Aeminium programmers specify dependencies rather than control flow, there is no need to engage in difficult, error-prone, and low-level reasoning about execution order or thread interleavings. Developers can instead focus on the design of the program, and benefit as the runtime automatically extracts the concurrency inherent in