I was going to pimp Indigo
, which is awesome home automation software, under the assumption if anyone would do it they would.
According to them, HomeKit has hardware requirements the Mac doesn't meet, so Macs can't be used with it.
There's a hardware HomeKit "hub" made by Insteon which Indigo could theoretically interface with, but it's low priority for them to implement because the communication would only be "one-way". You could use Indigo to trigger HomeKit, but you couldn't use HomeKit clients to trigger Indigo.