Microsoft CEO Satya Nadella spoke about the company embracing all developers and platforms at the annual Build conference. Source: Microsoft

At the annual Microsoft (MSFT -0.40%) Build developers' conference, CEO Satya Nadella today kicked things off by showing some of the first code ever written by the company's founders. He used that to reflect a bit on the past, but the highlight of his speech was his vision for the future.

In his remarks, and those of others, it became clear this is a different Microsoft -- a company more concerned about reaching the broadest possible customer base than about keeping people locked into the Windows ecosystem. 

What: Perhaps the most telling area for the company's new open environment was the care given to explain how its Azure cloud platform supports all languages, operating systems, and computing environments.

"We aspire to build an intelligent cloud back end for the world's applications running on all devices," Nadella said. The CEO said he wanted to create a cloud system in which "every developer on every platform can build intelligent apps."

Scott Guthrie, Microsoft's executive vice president for the cloud, came on stage after Nadella to expand on his boss's opening remarks and explain how developers can use Azure. He said Microsoft's cloud was agnostic on programming language, device, framework, and operating system. Guthrie also told the crowd of developers that Azure even allows users to work across other platforms on the cloud.

"We allow you to put all of your app in Azure or support hybrid deployments that span on-premises [servers] or other clouds," he said. 

So what: Nothing has changed for Azure except positioning. Microsoft, under former CEO Steve Ballmer, made little effort to reach customers using other operating systems or platforms. The company's entire goal for decades was to keep people in the Windows ecosystem. 

By encouraging every and any platform, OS, device, and programming language to be available on its cloud, Microsoft has shown it is embracing a computing world with fewer walls. That not only represents a huge philosophical change -- one Nadella has also pushed with Office by bringing it to Apple iPads and iPhones, as well as devices running Google's  (GOOG 0.43%)Android OS -- it represents a much broader potential customer base.

Microsoft isn't just allowing users of competing platforms and operating systems on its cloud; it's welcoming them. 

Now what: Azure has proven popular, but the challenge that remains is whether the company can keep up with Amazon.com's cloud platform, Amazon Web Services. That rival offering has been expanding by driving prices down. The remarks at Build, however, clearly show Microsoft wants to compete with the online retailer for all developers, not just those working on its proprietary platforms. 

That should make developers who were drawn to AWS simply because it wasn't Microsoft pause and at least look at Azure.

"Azure enables you to use the best of the WIndows ecosystem and the best of the Linux ecosystem," Guthrie said. "Azure allows you reuse the skills you have regardless of the programming languages you use."

That sort of language would have been, if not forbidden, certainly not encouraged at Microsoft less than two years ago. It's a sign that the company truly understands that the days of Windows' dominance being worth protecting are over.