Exporter::Tiny will stop auto-loading B soon
XS implementation for Enum - benchmarks at https://gist.github.com/tobyink/dfdf9bb826a530781e3d
XS for parts of Types::Common::* - benchmarks at https://gist.github.com/tobyink/dcc15cf283c90c749501
unify _USE_XS/_USE_MOUSE logic