Obviously that's not the hard part. Building your own Twilio is. I want to depend on multiple service providers, like you can do with Asterisk or FreeSWITCH.

Obviously that's not the hard part. Building your own Twilio is. I want to depend on multiple service providers, like you can do with Asterisk or FreeSWITCH. When X provider fails use Y provider. When Y provider is cheaper use Y. That's the true power of openness which OpenVBX has a vested interest in not providing.