Behind Windows 11 Beats a Heart from 30 Years Ago: Says Microsoft’s CTO

In 2026, collective expectations were geared towards lunar stations and flying cars, but the technological reality governing our PCs is decidedly more anchored to the past. These words were spoken by Mark Russinovich, Chief Technical Officer of Microsoft Azure and a historic figure in the Windows ecosystem, who recently reflected candidly yet pragmatically: the "bedrock," the rock on which the entire structure of Windows 11 rests, remains the ancient set of Win32 APIs.

We are talking about code written in the mid-1990s, a technology that not only survives after three decades but is described by the CTO as "more relevant than ever". This admission, which came through social media as part of a broader discussion, represents a strategic acknowledgment from Redmond, which seems to want to adopt a more transparent approach towards an increasingly skeptical user base tempted by alternatives like Linux or macOS. The persistence of Win32 is the result of an enormous ecosystem that has built its successes on this fundamental layer; removing or replacing it has historically proven a task beyond even Microsoft’s capabilities.

The Heavy Legacy of Win32: The Heart of Windows 11 Still Beats to a '90s Rhythm

This isn’t the first time Microsoft has tried to sever its umbilical cord with the past. Russinovich explicitly recalled the era of Windows 8, during which the company attempted to force a transition to WinRT. The goal was to completely reboot the Windows API surface, seeking to modernize the approach to software development. However, that gamble did not bear the expected fruits. The ecosystem’s resistance and the depth to which Win32 is integrated into business and productivity logics made WinRT a parenthesis rather than a revolution.

Did anyone expect Win32 to still be going strong in 2026? Mark Russinovich explains why its deep roots in Windows—and the massive ecosystem built on top—have given it serious staying power. Turns out “legacy” can still mean essential.

SysInternals site
Microsoft Dev Docs (@docsmsft)
May 6, 2026

Today, Windows 11 is approaching a 75% market share, and at the same time, it has to contend with fierce criticism regarding the performance of the core components of the system and its reliability. Management seems to have understood that the path of "forced modernization" (first of all, the controversial evolution into a heavily AI-based "agentic OS" proposed last November) is not enough to convince enthusiasts if the system's foundations show signs of fatigue.

To address these challenges, Microsoft has initiated a deep internal transformation, almost a return to the origins of engineering culture. The goal is to make Windows 11 extremely responsive while maintaining compatibility guaranteed by that thirty-year-old code that Russinovich himself helped write. Tools like Sysmon and ZoomIt, born in 1996 from the hands of the CTO, are still integrated today in Windows and PowerToys, respectively. This is not seen just as a limitation, but as proof of the robustness of a programming logic that has withstood decades of hardware evolution. The challenge for Redmond in 2026, therefore, is to optimize that rock to ensure that the stability of the past can support the performance required by the future.