Is there a good online source on rotating detonating pulse engine?
The idea seems fairly simple. Here's a [icture from one article and an explanation from another.

From Ars Technica

Micro-injectors squirt a pressurized mixture of fuel and air into a combustion chamber the shape of a long ring (annular cylinder). Then, this gas mixture explodes, with the explosion spinning around the circumference at supersonic speeds. The high pressure produced by the detonation forces exhaust gases upwards (in this diagram) and out of the chamber, where they expand through a nozzle and produce thrust that can be used to push a turbine or aircraft.
Unlike a PDE, which requires repeatedly initiating detonations, an RDE only requires one detonation that spins around and around the chamber, continuously producing thrust.

So there's no conventional turbomachinery. The detonation wave moves in a circle round the chamber, jumping from injector to injector. The only moving parts are the fuel injector pumps. I'm not sure how you throttle it, though.