What tech stack does Microsoft use?
Microsoft's engineering core is, unsurprisingly, its own platform: C# and the .NET ecosystem on the backend, TypeScript/JavaScript with React and its own Fluent UI on the frontend, and Azure as the cloud. The detail below is detected from public signals — the Microsoft engineering blogs, open-source repos on GitHub, job postings, and stack-analysis sites — so it is directional rather than an internal inventory.
- Frontend
- TypeScript, React, Fluent UI
- Backend
- C# / .NET, ASP.NET Core (plus Java, Go, Rust, C++)
- Cloud
- Microsoft Azure (first-party)
- Data
- SQL Server, Azure SQL, Cosmos DB, Microsoft Fabric
- Critical path
- Azure AI / OpenAI models, Kubernetes (AKS)
- Developer tooling
- GitHub, Visual Studio, VS Code, Azure DevOps
What technologies does Microsoft use?
A predominantly first-party stack: C#/.NET and Azure at the core, TypeScript/React on the frontend, and its own data and AI services.
- TypeScript· Frontend
- React· Frontend
- Fluent UI· Frontend
- C# / .NET· Backend
- ASP.NET Core· Backend
- C++· Backend
- Rust· Backend
- Go· Backend
- Microsoft Azure· Infrastructure
- Azure Kubernetes Service (AKS)· Infrastructure
- SQL Server / Azure SQL· Data
- Cosmos DB· Data
- Microsoft Fabric· Data
- Azure OpenAI / Copilot models· AI
- .NET MAUI / React Native· Mobile
- GitHub / Azure DevOps· DevOps
Sources:Understanding the Microsoft technology stack (Ful.io)Microsoft open-source repositories (GitHub)
What does Microsoft use on the backend and infrastructure?
The backbone is C# and .NET (with ASP.NET Core for services), the language that dominates Microsoft engineering job postings and powers large parts of Windows, Azure, Office, and enterprise tooling. Performance-critical and systems work also uses C++, and Microsoft has increasingly adopted Rust for memory-safe systems components, plus Go in some cloud services.
Infrastructure runs on Microsoft's own Azure cloud, including Azure Kubernetes Service for container orchestration. This first-party posture is a deliberate signal: Microsoft eats its own cloud, and its largest single compute customer relationship — the OpenAI partnership — also runs on Azure.
What does Microsoft use on the frontend, data, or GTM tooling?
On the frontend, TypeScript and React are widely used across web apps and the Microsoft 365 / Teams surfaces, often paired with Microsoft's own Fluent UI design system. Data and analytics lean on SQL Server and Azure SQL, Cosmos DB for distributed workloads, and the newer Microsoft Fabric analytics platform.
For developer and GTM tooling, Microsoft runs on its own products — GitHub and Azure DevOps for source and CI/CD, Visual Studio / VS Code as editors, and Dynamics 365 plus the Microsoft 365 / Copilot stack internally for CRM and business operations.
What Microsoft's stack means if you sell to them
Microsoft has an extreme build-and-own-it posture: it controls the OS, the cloud, the database, the IDE, the design system, and increasingly the AI models. Pitching a generic, undifferentiated alternative to something Microsoft already builds (cloud, IDE, CRM, identity) is a hard sell — it will usually prefer its own product or build its own.
The openings are at the edges and at scale: specialized infrastructure (silicon, networking, datacenter, security), AI/data tooling that complements rather than competes with Azure, and anything that helps it operate at hyperscale. Map your pitch to where Microsoft does not want to build, and expect deep technical due diligence and a preference for Azure-native or interoperable solutions.
As of June 2026.Sources:Understanding the Microsoft technology stack (Ful.io)Microsoft open-source repositories (GitHub)
Microsoft — frequently asked questions
