Microsoft has taken a first step toward its long-term goal of merging its Microsoft Account and Azure Active Directory cloud identity services.

On August 12, Microsoft made available a public preview of its converged programming model between the two.

"If you are a developer, this will make it WAY easier for you to write applications that work with both Microsoft Account and Azure AD Accounts," said Alex Simons, Director of Program Management for Microsoft Identity and Security Services, in a new blog post.

The Microsoft Account is Microsoft's cloud identity service for consumers; Azure Active Directory is Microsoft's identity service for businesses. Currently, developers have to integrate their apps differently with each stack.

With the new app model preview, it is possible to sign-in both personal and work users with a single button, officials said. The new model supports OAuth 2.0 and OpenID Connect 1.0 and normalizes requests and responses across Microsoft Account and Azure AD.

Not every application that currently interfaces with Azure AD or Microsoft Account is currently supported in the first preview. But the plan is to have a single authentication model and unified REST programming interface between the two different identity services, and to move Microsoft's own applications to the new sign-in experience over time. Until that happens, Microsoft plans to continue to fully support the existing protocols, software development kit and current app model tools.

Microsoft officials haven't talked about when they expect the two ID services to finally be converged.