Effect typing can achieve capability security statically, but I've also frequently seen capabilities used to describe dynamic capability systems via various methods involving passing capabilities down as reified objects of some sort.
This of course also depends on some related static guarantees that a function can't access ambient capabilities not passed directly in their arguments, but this is a much simpler static guarantee than effect typing and doesn't require specific analysis over normal parameter types.
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Effect typing can achieve capability security statically, but I've also frequently seen capabilities used to describe dynamic capability systems via various methods involving passing capabilities down as reified objects of some sort.
This of course also depends on some related static guarantees that a function can't access ambient capabilities not passed directly in their arguments, but this is a much simpler static guarantee than effect typing and doesn't require specific analysis over normal parameter types.