hjul (cargo): Simple and efficient timer abstraction on top of `mio-extra`. Every timer is associated with a callback which is executed whenever the timer expires, timers can be stopped and reset, in which case the callback might be executed multiple times. The primary intended application is one in which timers have a bounded maximum duration (e.g. at most 10 minutes) and have to be cancelled and restarted very often. 
Keywords: mio|callback|timer-wheel|timer|mio-extra