Rust Is Tier-1 Language at Microsoft

Rust code now integrates directly with the Windows native compilation toolchain, simplifying hybrid development.

Microsoft has officially designated Rust as a Tier-1 language, alongside C++, C#, and TypeScript. This elevates Rust's status, providing internal teams with a streamlined path from development to production, including secure toolchain builds, advanced developer tooling, robust workflows, deep platform integration, and compliance with Microsoft's stringent security requirements. A key development enabling this is rustc_codegen_utc, a new backend for the Rust compiler (rustc). This backend directly connects Rust to the Microsoft Visual C++ (MSVC) compiler's backend, enabling seamless interoperability between Rust and C++ code. Previously, other platforms could achieve similar integration via LLVM, but rustc_codegen_utc provides Windows-native C++ projects using MSVC with a shared backend. This innovation aims to reduce maintenance costs and accelerate the adoption of new platform features across both languages, particularly benefiting hybrid Rust/C++ projects that are expected to remain common for years. Over 100 Microsoft projects are already utilizing this new infrastructure.

The designation of Rust as a Tier-1 language at Microsoft signifies a maturing ecosystem where memory safety and performance are becoming increasingly paramount for core systems development. The introduction of rustc_codegen_utc is a strategic move, leveraging decades of investment in the MSVC backend to provide Rust with out-of-the-box compatibility for Windows-specific features like post-link compliance and hotpatching. This alignment reduces duplicated engineering efforts and ensures Rust can directly benefit from ongoing platform evolution in areas like security, diagnostics, and servicing, especially crucial for hybrid Rust/C++ projects.

This development establishes a shared compilation backend for Rust and C++ on Windows, mirroring the LLVM integration available on other platforms. It significantly enhances interoperability, enabling seamless cross-language inlining, optimization, and debugging for hybrid projects. The direct connection to the MSVC backend also means Rust code benefits from platform hardening and code security features without requiring parallel implementations. This unified foundation is poised to accelerate the adoption of Rust in critical Windows components, from firmware and kernel to microservices.