F>Переписать куски браузера (Firefox, Chrome) или даже ОС (Windows, Linux) — вроде не удивляет. Но офис -- это что-то новое. 20 лет назад переписывали С++ на C#, теперь C# на Rust.

Вакансия про облачную часть "офиса" (Office 365).

The Substrate App Platform group is part of M365 Core Platform organization.

Но переписывают действительно с C# на Rust.

Responsibilities will include guiding technical direction, design and implementation of Rust component libraries, SDKs, and re-implementation of existing global scale C# based services to Rust.

This is one of the rare opportunities to learn, grow and lead by building mission critical high-scale subsystems from scratch.

Про Субстрат:

The Office 365 Substrate is a poorly understood part of Microsoft's Cloud Office system. The substrate is a critical part of enabling services that run across different applications like Exchange Online, SharePoint Online, Teams, and so on.
Functionality like search, information protection, data governance, and eDiscovery is a lot harder when you have multiple moving parts. The substrate gives cohesion and coherence to what could otherwise be a tangled mess.

https://techcommunity.microsoft.com/t5/microsoft-365/exploring-the-office-365-substrate/m-p/1044294

F>Переписать куски браузера (Firefox, Chrome) или даже ОС (Windows, Linux) — вроде не удивляет. Но офис -- это что-то новое. 20 лет назад переписывали С++ на C#, теперь C# на Rust.

Вакансия про облачную часть "офиса" (Office 365).

The Substrate App Platform group is part of M365 Core Platform organization.

Но переписывают действительно с C# на Rust.

Responsibilities will include guiding technical direction, design and implementation of Rust component libraries, SDKs, and re-implementation of existing global scale C# based services to Rust.

This is one of the rare opportunities to learn, grow and lead by building mission critical high-scale subsystems from scratch.

Про Субстрат:

The Office 365 Substrate is a poorly understood part of Microsoft's Cloud Office system. The substrate is a critical part of enabling services that run across different applications like Exchange Online, SharePoint Online, Teams, and so on.
Functionality like search, information protection, data governance, and eDiscovery is a lot harder when you have multiple moving parts. The substrate gives cohesion and coherence to what could otherwise be a tangled mess.

https://techcommunity.microsoft.com/t5/microsoft-365/exploring-the-office-365-substrate/m-p/1044294

В обсуждениях на реддите есть еще любопытая ссылка про портирование компонентов MS Windows на Rust
https://old.reddit.com/r/rust/comments/12yg3cp/microsoft_rewriting_core_windows_libraries_in_rust/jhmz12f/