Home Archive AI agents, EF Core joins, and performance – .NET News Daily Issue #394 (Feb 18, 2026)

Editor's note

I pulled together a pretty mixed issue this time, which is exactly how I like it. The VS Code multi-agent orchestration piece and the Copilot testing launch both show where .NET tooling is headed, while the EF Core join article is a practical win for day-to-day query work.

AI agents, EF Core joins, and performance

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Today's Articles

Hands On with New Multi-Agent Orchestration in VS Code

https://visualstudiomagazine.com/Articles/2026/02/09/Hands-on-with-New-Multi-Agent-Orchestration-in-VS-Code.aspx

A proof of concept shows how multi-agent orchestration in Visual Studio Code 1.109 can turn a fragile, one-pass AI workflow into a more reliable, auditable process by breaking long tasks into smaller,...

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C# 13 & .NET 9 — Part 14: Web Services, RESTful API, gRPC, Pagination in APIs, Postman and Swagger

https://medium.com/@ddemirugur/c-13-net-9-part-14-web-services-restful-api-grpc-pagination-in-apis-postman-and-swagger-b52427a7e3e2?source=rss------dotnet-5

This article is based on Chapter 14: Website Development Using MVC Pattern

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Testing for Memory Allocations in Unity

https://medium.com/@davidreimer/testing-for-memory-allocations-in-unity-fbb4e8bb3f53?source=rss------csharp-5

How to create a test to know if some code allocates in Unity

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Understanding Domain-Driven Design (DDD) in .NET

https://medium.com/@rserit/understanding-domain-driven-design-ddd-in-net-95ec22eab8c6?source=rss------dotnet-5

Domain-Driven Design is a domain-centric approach that treats the software development process not merely as a coding activity, but as a…

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How LeftJoin and RightJoin Work in EF Core .NET 10

https://www.roundthecode.com/dotnet-tutorials/how-leftjoin-rightjoin-work-ef-core-dotnet-10

Learn how LeftJoin and RightJoin work in EF Core .NET 10, replacing complex GroupJoin patterns and simplifying left and right joins in LINQ. The page How LeftJoin and RightJoin Work in EF Core .NET 10...

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GitHub Copilot Testing for .NET Brings AI-powered Unit Tests to Visual Studio 2026

https://devblogs.microsoft.com/dotnet/github-copilot-testing-for-dotnet-available-in-visual-studio/

GitHub Copilot testing for .NET is now generally available in Visual Studio 18.3. This AI-powered testing experience helps you generate, build, fix, and run unit tests quickly and efficiently. With fl...

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Why Enterprises Prefer .NET Development Services: Real Industry Insights & Benefits

https://medium.com/@evansrose623/why-enterprises-prefer-net-development-services-real-industry-insights-benefits-8699b5c37373?source=rss------dotnet-5

In a digital-first world where performance, security, and scalability matter more than ever, enterprises are constantly evaluating the…

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.NET Performance Superpower: Understanding ValueTask (and When Not to Use It)

https://medium.com/@siddhi11.aswale/net-performance-superpower-understanding-valuetask-and-when-not-to-use-it-2ca11d3ef10e?source=rss------dotnet-5

.NET Performance Superpower: Understanding ValueTask (and When Not to Use It)

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Dotnet Core Identity With .NET CLI

https://ravindradevrani.medium.com/dotnet-core-identity-with-net-cli-f64d89462264?source=rss------dotnet-5

Aspnet core identity provides an UI to registration, login, manage users, password, external authentication (google, twitter, facebook…

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Ready to explore how AI is transforming the .NET world?

https://medium.com/@molletibalu/ready-to-explore-how-ai-is-transforming-the-net-world-3965ba7a1b0d?source=rss------dotnet-5

🚀 Ready to explore how AI is transforming the .NET world? Join our FREE workshop on AI with .NET and discover why .NET developers are in…

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What is Semantic Kernel and how does it help build AI agents in .NET?

https://www.c-sharpcorner.com/article/what-is-semantic-kernel-and-how-does-it-help-build-ai-agents-in-net/

Semantic Kernel simplifies AI agent creation in .NET. This open-source SDK connects your code to AI models, enabling powerful features like RAG, plugins, and more.

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A Comprehensive Technical Analysis of .NET Framework and Modern .NET

https://medium.com/@nima.hamdi/a-comprehensive-technical-analysis-of-net-framework-and-modern-net-fdc81329d32f?source=rss------dotnet-5

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What Is A Message Queue? RabbitMQ + MassTransit Integration in .NET 8

https://medium.com/@mariammaurice/what-is-a-message-queue-rabbitmq-masstransit-integration-in-net-8-de9c7f25db3a?source=rss------csharp-5

The Complete Guide to Async Messaging, Sagas, and Event-Driven Architecture

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I Misused C# Records for 12 Months — The Painful Lessons Real Production Code Taught Me

https://blog.stackademic.com/i-misused-c-records-for-12-months-the-painful-lessons-real-production-code-taught-me-c02dd8cb7991?source=rss------csharp-5

Why my obsession with immutability backfired in ASP.NET Core projects, broke EF Core tracking, and forced a refactor I never saw coming. Continue reading on Stackademic »

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Jasen's take on today's picks

Hands On with New Multi-Agent Orchestration in VS Code

VS Code’s multi-agent orchestration makes AI workflows feel less like prompts and more like traceable work.

C# 13 & .NET 9 — Part 14: Web Services, RESTful API, gRPC, Pagination in APIs, Postman and Swagger

A solid REST/gRPC refresher for anyone building APIs, with pagination and tooling basics in the mix.

Testing for Memory Allocations in Unity

If you care about allocations, the Unity testing approach is a useful pattern to steal.

Understanding Domain-Driven Design (DDD) in .NET

DDD explanations are easy to overcomplicate; this one keeps the focus on modeling the domain.

How LeftJoin and RightJoin Work in EF Core .NET 10

EF Core LeftJoin/RightJoin is the kind of practical upgrade that saves a lot of GroupJoin boilerplate.

GitHub Copilot Testing for .NET Brings AI-powered Unit Tests to Visual Studio 2026

Copilot Testing for .NET is the most immediately useful AI item here: faster test generation, fewer setup steps.

Why Enterprises Prefer .NET Development Services: Real Industry Insights & Benefits

Identity via the CLI is still one of those things people need written down clearly.

.NET Performance Superpower: Understanding ValueTask (and When Not to Use It)

ValueTask is powerful, but the real value is knowing when not to reach for it.

Dotnet Core Identity With .NET CLI

A good reminder that records are a tool, not a default answer, especially once EF Core gets involved.

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