Visual C# .NET Blog

C# 15 ships with .NET 11. It adds union types, closed hierarchies, a preview of the updated unsafe model, and a few smaller changes that remove everyday ceremony. The post Explore new features available in C# 15 preview appeared first on .NET Blog.

Meet the open-source polyglot testing agent that learns from a repository, writes unit tests, and checks that they build and pass. The post From generated code to trusted code with a unit-test agent appeared first on .NET Blog.

MCP C# SDK v2.0 implements the 2026-07-28 specification with a stateless-first protocol, standardized HTTP headers, and Multi Round-Trip Requests for interactive tools, all while staying backward compatible. The post Announcing v2.0 of the official MCP C# SDK appeared first on .NET Blog.

Catch up on all the .NET sessions from Microsoft Build 2026 covering .NET 11, union types in C#, AI building blocks, the agentic web, .NET MAUI, and more! The post .NET at Microsoft Build 2026: Must watch sessions appeared first on .NET Blog.

The `unsafe` keyword is being redesigned to mark caller-facing contracts rather than just syntax. Safety obligations between callers and callees become visible and reviewable. The model is motivated by the rise of AI-assisted code generation and arrives as a preview in .NET 11. The post Improving C# Memory Safety appeared first on .NET Blog.

Adding caching to your application architecture can significantly improve key performance metrics, cut latency, and reduce load across downstream systems. In this walkthrough, we highlight the latest caching best practices and incorporate these design patterns into a reusable .NET application that you can reference when adding new capabilities to your application stack. The post High-Performance Distributed Caching with .NET and Postgres on Azure appeared first on .NET Blog.

C# 15 introduces union types — declare a closed set of case types with implicit conversions and exhaustive pattern matching. Try unions in preview today and see the broader exhaustiveness roadmap. The post Explore union types in C# 15 appeared first on .NET Blog.

Discover what’s new in the v1.0 release of the official MCP C# SDK, including enhanced authorization, richer metadata, and powerful patterns for tool calling and long-running requests. The post Release v1.0 of the official MCP C# SDK appeared first on .NET Blog.

Azure DevOps enhanced support for Microsoft.Testing.Platform, from running tests to publishing results! The post Microsoft.Testing.Platform Now Fully Supported in Azure DevOps appeared first on .NET Blog.

Learn what features are in C# 14, which ships as part of .NET 10. The post Introducing C# 14 appeared first on .NET Blog.