Would that be ok to allow extend to take kwargs and/or map params for proto+mmaps (right now it's kw-args only) and leverage the underlying auto-conversion ? basically changing the signature from [atype & proto+mmaps] to [atype & {:as proto+mmaps}] ?

it's quite handy when you have a map as a "proto+mmaps"

pb I am trying to solve: making extend calls easier with maps, since sometimes when you use it the proto-mmap might be the result of composition/mixins

I know I can just (apply extend type (into [] cat proto-mmap-map) for now, but that seems that changing the signature would be harmless (and allow both)