Why Amazon Will Make or Break Twilio

twilio_logoIt’s true that Twilio just named successful Silicon Valley prognosticators Founders Fund and Mitchell Kapor as initial investors, but the real Twilio story lies in its infrastructure. Or rather, its lack of infrastructure.

The San Francisco-based startup hosts all the computing functions of its web developer-friendly telephony service on Amazon Web Services (s AMZN), a business model that enables Twilio to differentiate itself even further from its voice API cohorts. Upfront CAPEX savings by Twilio trickle down to users in the form of an inexpensive per-call pricing model. By leveraging Amazon’s cloud platform, Twilio’s infrastructure grows (and shrinks) right along with customer demand.

As with all things invoking “cloud computing,” however, there’s a catch: Twilio customers’ applications are at the mercy of Amazon. If EC2 goes down, phone calls don’t go through. CEO Jeff Lawson’s faith in Amazon might provide some comfort (“If I say, ‘I’m a startup and I run my own data center,’ you should run like hell,” he joked to me), but the prospect of uncontrollable downtime might give users pause if their telephony apps are tied to measurable revenue. Twilio doesn’t offer an SLA, either.

That said, Lawson says Twilio’s platform has been up and running at 100 percent since the company launched in November, and users can check current availability at

Another noteworthy aspect of Twilio is that it might not be alone for long on the development front. Voxeo will announce today that it’s launching a platform to let developers write telephony apps in standard web languages.