CAPI and constraint solver

I looked up the CAPI user guide to figure out the constraint solver system it may use. There is nothing mentioned in it, per se.

Does it use a proprietary constraint solver or Cassowary? How does it compare to say Garnet/Cocoa Autolayout/Enaml: the latter two use Cassowary.

This is a question that popped up while 'struggling' with Cocoa Auto layout :-).

Thanks,

Deepak
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