Microsoft annoints Rust as a 'Tier 1' internal language

Microsoft has designated the Rust programming language as a Tier 1 internal language, joining the ranks of C++, C#, and TypeScript. Victor Ciura, a principal engineer at Microsoft, explained that this designation means Rust is now among the best supported languages for internal development at the company. Microsoft has already integrated Rust into over 100 project repositories and has built Oxidizer, a set of crates to build scalable services in Rust, which have been used to improve Microsoft 365 core services like Outlook, Word, Excel, OneDrive, and SharePoint.

The company also relies on Rust for the Copilot tech stack. However, there is still significant work ahead for Microsoft, particularly in addressing memory issues in Windows code. Rust was created by Mozilla developer Graydon Hoare in 2006 as a high-performance language that helps guard against memory bugs. Microsoft has made strides to make Rust comfortable on its native platform, Visual C++, by building rustc_codegen_utc, a custom Rust compiler code-generation backend that integrates with MSVC's internal toolchain for Windows.

This allows Rust to build on the same platform investment as C++ without requiring a parallel implementation of every Windows-specific capability. Despite the progress, Microsoft engineers will face challenges when mixing Rust and C++ code, as the Rust compiler does not typically cover pointers into C++ memory allocations. Mark Russinovich, Microsoft Azure CTO, highlighted that over 70% of Windows CVEs are memory issues, emphasizing that no amount of improvements to C and C++ can match the inherent security benefits of Rust.