Update December 24: Galen Hunt, a Distinguished Engineer at Microsoft, has recently found himself at the center of attention following his ambitious proposal to replace all C and C++ code within the company. In light of the unexpected interest, he has taken to LinkedIn to clarify his intentions and the broader goals of Microsoft regarding programming languages.
In his updated post, Hunt emphasizes that Windows will not undergo a complete rewrite in Rust with the assistance of AI. Instead, he outlines that the focus is on developing technology to facilitate smoother transitions between programming languages. He characterizes these efforts as part of a “research” initiative at Microsoft.
It is important to note that Hunt’s original assertions were bold and open to interpretation by various media outlets. While a complete overhaul of Windows may not be on the table, it is likely that Hunt and his colleagues are aiming for the eventual removal of all C and C++ code from Microsoft’s codebases, including the core components of Windows. This initiative may involve the use of automated tools, which some may refer to as AI, alongside the integration of Rust.
Original article, December 23:
There appears to be a significant push within Microsoft to eliminate all C and C++ code by the end of the decade. Galen Hunt has proposed a bold vision where AI and algorithms would facilitate the mass rewriting of codebases into Rust, encapsulated in a catchy slogan: one engineer, one month, one million lines of code.
Microsoft’s motivation for this transition is rooted in a desire to address technical debt accumulated over decades, predominantly in the form of legacy code written in C and its derivatives, C++. The aim is not only to modernize but also to mitigate a specific class of vulnerabilities—memory-related bugs. Global authorities have long urged tech companies to prioritize memory safety in their development roadmaps, which aligns with the adoption of Rust, a language designed with memory safety in mind.
To tackle this technical debt, Microsoft is leveraging modern tooling and has developed a robust infrastructure that combines AI agents with algorithmic analysis. Hunt notes that this infrastructure is already operational at scale for challenges such as code comprehension.
Urgency for memory-safe code
This strategic shift is not merely a reaction to external cybersecurity warnings. Earlier in 2023, Microsoft announced plans to rewrite portions of the Windows kernel in Rust, following Azure CTO Mark Russinovich’s directive to halt new C/C++ projects. Russinovich had previously declared that Microsoft was “all-in on Rust,” a sentiment that has since led to a significant expansion of the language’s use within the company.
The rationale behind this transition is clear: memory errors in C and C++ are responsible for an estimated 70 percent of vulnerabilities in Microsoft products. Rust addresses these issues by incorporating memory safety features without compromising performance. While it is still possible to create memory leaks in Rust, it is less straightforward than in C and C++, and adherence to best practices should render developers immune to memory safety issues.
Russinovich has indicated that Microsoft is working on “more automated translation from C and C++ to Rust using LLMs.” Hunt’s recent LinkedIn post serves as a tangible follow-up to this initiative, as he actively seeks a Principal Software Engineer to help realize this vision.
Job opening requires Rust expertise
The job specifications are quite clear: candidates should ideally possess a minimum of three years of experience in writing systems-level code in Rust. While experience with compilers, databases, or OS implementations is highly desirable, it is not mandatory. However, the selected candidate must be willing to develop expertise in compiler technology as part of the team.
Hunt’s Rust refactoring team operates within the Future of Scalable Software Engineering group, part of Microsoft CoreAI’s Engineering Horizons organization. Their mission is to “build capabilities that enable Microsoft and our customers to eliminate technical debt at scale.” The team collaborates with internal customers and partners to develop new tools and techniques, which are subsequently deployed across the company and the broader industry.
Rust adoption is growing worldwide
Microsoft’s commitment to Rust is reflective of a growing global enthusiasm for the language. According to JetBrains, there are currently 2.3 million developers using Rust, with 709,000 considering it their primary programming language. In enterprise settings, adoption has surged by 68.75 percent. In system programming, Rust’s market share has increased from 1.05 percent in 2024 to 1.47 percent in 2025, marking a relative growth of 40 percent. Although Rust is more complex than languages like Python and lacks the extensive legacy of C and C++, its low-level nature minimizes abstraction layers, making it suitable for critical systems like kernels, IoT devices, and system drivers.
Major tech companies such as Google, Amazon, Dropbox, and Cloudflare are increasingly integrating Rust into their critical infrastructure. Google has even invested million in the Rust Foundation to enhance interoperability between C++ and Rust. This interplay between old and new programming paradigms has introduced some friction in the development of the Linux kernel, particularly as seasoned developers are accustomed to reviewing only C and C++ code. The Rust project itself faces its own set of challenges, yet the need for a stable future in IT infrastructure is becoming ever more pressing as tech giants continue to adopt this innovative language.