In the tech industry, the practice of a software company's employees using in-house software for daily tasks so that they can personally test it and work out bugs before releasing it to the public is called "dogfooding". This practice normally involves the earliest of early alpha software, coming out earlier and changing faster than even open alphas and public betas. While Office Insider has allowed Microsoft Office 365 customers to check out software that hasn't quite hit the public release channel yet, the timeline for releases was more in line with beta testing, and included software that had already been tested and tweaked by both regular employees and specialized testers. For those who want to use software that's even fresher, Microsoft is opening up their employee testing builds to the public in the form of Office Insider Fast.
The Office Insider program only launched last November, but has already proven popular enough to bring in over 100,000 unique bits of feedback from customers, making it about as successful as a public beta testing opt-in program could hope to be. While enterprise customers have access to fairly early builds and quick patches from upstream through the First Release option, the unveiling of Office Insider Fast marks the first time that end users on the home front have had officially sanctioned access to Microsoft software that has yet to be beta tested by employees.
The ability to sign up for Office Insider Fast will be coming out within the next few days for Mac users, as well as Windows desktop and Windows Mobile. Microsoft's press release indicates that the capability will be coming to Android and iOS at some point, but a definitive date is not on the table for the time being. The preview builds provided through Office Insider Fast will be without any official support, meaning that the only solution to most bugs will be to report them and wait for a fix. Still, there are many users who either would love to help Microsoft make Office as bug-free as possible, and even more users who value cutting-edge software. For these crowds, Office Insider Fast is where it's at.