The .NET Insider – Issue 18

.NET 11 Preview 1 is here, introducing early improvements across the runtime, SDK, and developer tooling. This first preview gives developers a look at upcoming performance enhancements, platform updates, and new capabilities shaping the future of .NET applications. Now is the time to explore, test, and prepare for what’s next in the .NET ecosystem.

This article shows how developers can build AI agents using the GitHub Copilot SDK together with the Microsoft Agent Framework. It covers agent architecture, orchestration, and real-world patterns for creating intelligent, tool-aware, and extensible agents that integrate seamlessly into modern .NET and Microsoft ecosystems.

The Visual Studio January update delivers a smoother and more productive editor experience, with improvements to code navigation, IntelliSense, formatting, and overall responsiveness. These enhancements help developers write, read, and refactor code faster—right where they spend most of their time.

Visual Studio Code now supports Model Context Protocol (MCP) apps, enabling developers to build and run context-aware, agent-driven applications directly in the editor. This update makes it easier to integrate AI tools, manage context, and create smarter developer workflows across languages and platforms.

GitHub Copilot now integrates deeper work context into your coding experience, connecting tasks, documentation, and project knowledge directly to your editor. This update helps developers get more relevant AI suggestions, reduce context switching, and build software faster with smarter, context-aware assistance.

This post introduces the foundational components for building AI-powered applications in .NET, including unified LLM access, vector data support, agent frameworks, and Model Context Protocol (MCP). It breaks down how these libraries work together to help developers design scalable, intelligent, and production-ready AI solutions in C#.

An announcement of .NET Framework 3.5 servicing updates on new versions of Windows.

This guide walks through building and deploying an application using .NET Aspire 1.3, covering distributed app setup, service orchestration, and cloud-ready deployment. A practical introduction for developers who want to simplify microservices development and improve observability in modern .NET systems.

This guide explores the best way to start a new .NET project in 2026, covering modern project templates, architecture decisions, tooling, and recommended defaults. Learn how to set up scalable, maintainable, and cloud-ready .NET applications using current best practices and ecosystem standards.

This article explains how to use keyed services in ASP.NET Core to register and resolve multiple implementations of the same interface using identifiers. Learn how keyed dependency injection improves flexibility, supports feature variations, and simplifies complex service selection scenarios in modern .NET applications.

This guide introduces Dapper Plus, an extension for Dapper that enables fast and efficient bulk insert, update, delete, and merge operations in .NET applications. Learn how to improve database performance and handle large datasets with minimal overhead while keeping your data access layer clean and efficient.

GitHub Copilot now supports AI-powered testing for .NET directly inside Visual Studio. Developers can generate unit tests, improve coverage, and accelerate test-driven development using intelligent suggestions tailored to their codebase. This update strengthens AI-assisted workflows across modern .NET applications.