Sounds like Duct is doing magic with config then?

@seancorfield I didn't trace it all the way back, but here's what I think is gonig on The config is assocd to the system after it's started, and I think that means that those keys in the config now live along side keys that point to components. Those are the same keys that components use to depend on each other...

https://github.com/duct-framework/duct/blob/master/duct/src/duct/util/system.clj#L17-L24

right where you linked, the config is being merged in to the system map (using into) before the system is started

the lifecycle protocol is extended the Object as no-ops, you can stick anything you want in the system map depend on it

@hiredman thanks. I never found reference to that use of component, but turned out to be handy, thanks for clarification!