How to support concurrent execution on rules? Is there a multirule?

Is there a method of declaring a rule that should execute it's prerequisites concurrently? What about defining a new multirule keyboard to support such an operation?

Assuming you can run all tasks as multitasks, you can turn everything into a multitask with rake -m. You can also generate a multitask on the fly from a rule. This all being said, I’d also welcome a multirule and even a multifile into my workflow.