Microsoft engineer walks back claim on eliminating C and C++: No plan to rewrite Windows

Microsoft Windows

A senior Microsoft engineer has clarified that the company is not planning to eliminate C and C++ from Windows by 2030, walking back claims that sparked widespread speculation across the tech industry.

Galen Hunt, a distinguished engineer at Microsoft, issued a clarification after his earlier LinkedIn post was widely interpreted as a roadmap to rewrite Microsoft’s core codebases using AI and Rust. According to Hunt, that interpretation went far beyond what he intended to convey.

In a follow-up statement, Hunt said his original message “generated far more attention than I intended” and stressed that Windows is not being rewritten in Rust, nor is there a company-wide plan to remove all C and C++ code within the decade.

Hunt explained that the work in question is a research initiative being conducted by Microsoft’s Future of Scalable Software Engineering group. The project is focused on developing tools that can enable large-scale code migration between programming languages, rather than targeting Windows specifically.

The internal goal of the research effort is ambitious. Hunt described it as aiming for “one engineer, one month, one million lines of code.” To reach that scale, the team is experimenting with a combination of AI agents and algorithmic infrastructure designed to analyse, translate and refactor codebases automatically.

Crucially, Hunt said this work is exploratory. It is not a committed product roadmap, nor is it tied to any timeline for Windows 11 or future versions of the operating system. While the team is actively hiring engineers with Rust experience to continue developing these capabilities, the research does not imply that Rust will replace C or C++ across Microsoft’s software stack.

The clarification follows a wave of reports that framed Hunt’s original post as a definitive declaration that Microsoft intended to rewrite its vast legacy codebase in Rust by 2030. Hunt said that characterisation was inaccurate and overstates both the maturity and the intent of the project.

Although Hunt’s research project is not a mandate for Windows, Microsoft’s broader interest in Rust is well established. The company has been gradually introducing Rust into parts of its products, particularly where memory safety and security are critical.

In 2023, Microsoft confirmed that some components of the Windows kernel were being rewritten in Rust. Separately, Azure chief technology officer Mark Russinovich has publicly said the company is “all-in” on Rust for new projects where it makes sense.

Rust is valued for its built-in protections against common classes of bugs, especially memory-related vulnerabilities that are historically associated with C and C++. These issues have been a major source of security flaws across the software industry, including in operating systems.

Hunt has also clarified that even within his research project, Rust is not necessarily the final destination. The aim is to make large-scale code translation feasible, regardless of source or target language, using AI-assisted tooling.

The episode highlights how easily experimental research can be mistaken for corporate strategy, particularly when it touches on sensitive topics like legacy code and security. Microsoft’s investment in AI-powered development tools is real, but the scope, timelines and outcomes remain fluid.

For now, C and C++ are not going anywhere inside Windows. Hunt’s work represents an exploration of what might be possible in the future, not a commitment to dismantle decades of existing engineering foundations.