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Highlights
.NET Conf 2026 Community Days Call for Presenters Is Open
The Agentic Road to Revenue
How can I remove the Close button from my window caption?
Latest posts
Introducing Foundry Dev Pack: One Command to Start Building on Microsoft Foundry
Foundry Dev Pack prepares your machine for Microsoft Foundry development with an all-in-one installer for the tools you need across the terminal, VS Code, and coding agents.
From Redis pressure to a healthier service
Lessons from an Azure Managed Redis migration for Copilot Studio agent flows: cache efficiency, client reliability, staged rollout, and lower costs.
PackageType: Main, Framework, Resource, Optional, Bundle
Every MSIX package is one of four package types: MSIX also supports Bundle packages. Bundles are somewhat different from those four package types: a Bundle is a container for one or more MSIX packages. Windows APIs nevertheless expose Bundle alongside the other package types when identifying packages. Each package type has its own behaviors, nuances, and rationale worthy of a dedicated discussion. We'll take a brief whirlwind tour of MSIX package types here and explore them in greater detail in future blog posts. What does imply? What does actually mean? MSIX packages have various properties and beh...
Today I will… improve test coverage
Today I want to look at how we can improve on the test coverage that we have in the Interview Coach application. This application has some unit tests in it already, but I'm sure there is room for improvement. Defining our baseline Before we start writing tests, it's a good idea to have a baseline of what our coverage is so that we can find out where the gaps are, rather than just writing tests "for the sake of writing tests". We can do this using the Analyze Code Coverage for All Tests, from either the Command Palette (CTRL + SHIFT + P) or the Tests menu. Running the analyzer, we can see where our coverage ...
Build an interview coach app with the GitHub Copilot SDK
An interview coach has to do more than ask questions. It needs to read a resume, follow up on an incomplete answer, and save enough context to give useful feedback at the end. Some of that work is conversation. Some of it requires calling an application service. The GitHub Copilot SDK lets you use the runtime behind Copilot CLI for that work inside your own application. You provide instructions and callable tools. Copilot handles the model interaction and resulting tool calls, while your application owns the interface and business workflow. For a developer building a personal assistant or an internal workflow, ...
Coding agents are picking Azure SQL Database
I went looking for Azure SQL Database in a recent coding agent benchmark, honestly unsure whether Microsoft SQL would show up. Armature ran a study where real coding agent CLIs (Claude Code, Codex, Cursor) were dropped into six synthetic-but-realistic repositories and asked to pick a database, then actually build with it. 356 runs were completed across three personas: vibe coder, junior developer, senior engineer. Every session is published, so you can replay the prompts, the searches, the commands, and the code. Azure SQL Database came in second! Not second behind AWS. Second behind Neon, and ahead of Amazon...
Performance Improvements in .NET 11
Take a tour through hundreds of performance improvements in .NET 11.
C++ in the Age of AI: Visual Studio at CppCon 2026
At CppCon 2026, we shared how Visual Studio is evolving to help you work more effectively with large C++ codebases, improve build and runtime performance, adopt the latest language features, and incorporate AI into your existing workflows. This post is a companion reading guide for our session, C++ in the Age of AI: How Visual Studio Is Evolving, with links to learn more about the features and improvements we discussed. We will update this post with the YouTube video once the recording of the talk is available. What's new in Visual Studio 2026 These two release roundups provide the most complete overview of ...
Share your .NET story with the community
Share how your team uses .NET to solve real problems and help us bring more community stories to .NET Conf 2026 and other .NET channels.
Why didn’t ReadDirectoryChangesW provide a way to correlate the two sides of a rename operation?
Perhaps it wasn't necessary, or perhaps it didn't occur to them that this a problem.
What’s New for C++ Developers in Visual Studio 2026 (18.7 – 18.10)
Over the past few months, we have continued shipping monthly Visual Studio 2026 releases, delivering improvements across all stages of the development cycle. In this blog post, we'll recap everything that changed from version 18.7 through 18.10 (released this month) that is relevant for C++ developers. This includes new tools for maintaining and navigating C++ projects, along with Git, GitHub Copilot, and debugging improvements that support the way large native codebases are built. Some headlines include the GitHub Copilot modernization experience (now generally available) to guide you through MSVC upgrades, a...
MulticloudDB SDK: Cross-cloud portability in the coding agent era
Building cross-cloud solutions with best-of-breed cloud-native databases means learning multiple SDKs, translating queries, handling different errors, and testing across providers. The Multicloud DB SDK for Java lets you share that work across Azure Cosmos DB, Amazon DynamoDB, and Google Cloud Spanner. You (or your coding agent) write CRUD and query logic against one Java API, with provider selection and connection settings in configuration. We demonstrated one application running unchanged across two providers at Azure Cosmos DB Conf 2026 on April 28, 2026, in MultiCloudDB: Write Once. Run Anywhere.. The SDK is...
Microsoft at CppCon 2026
Microsoft will be at CppCon 2026 in Aurora, Colorado, which is taking place from September 14 through 18. Join us for talks from Microsoft speakers and colleagues across the C++ community and visit the Microsoft booth Monday through Thursday to meet the team and discuss the tools, technologies, and challenges that matter to you. If you can't make it, you can still watch the talks later on YouTube. Survey Whether you are going to the conference or not, we also invite you to take our annual CppCon survey at aka.ms/cppcon/survey. Your feedback can help us improve our C++ developer tools and focus on solving the mo...
Building a Japanese LLM Evaluation Pipeline: Lessons from a Two-Day Hackathon
ISE hackathon produced a reusable Japanese LLM evaluation pipeline with multi-turn, facet-based scoring, cross-provider model support, and publication-ready benchmarking outputs.
How can I remove the Close button from my window caption?
Not through normal means.
MSVC C++23: constexpr cmath with LLVM Libc
Proposal P0533R9 made numerous math functions in the standard library compile-time evaluable in C++23. Implementing the feature required a good bit of time and effort, but MSVC is preparing its experimental implementation for the 14.52 build tools (compiler version 19.52)! We are still refining the feature, so expect the dust to settle only when this has shipped for production. The feature is enabled with a combination of the or later and compiler options. It is initially shipping as experimental and off by default because our implementation is powered by a new math library at compile-time and runtime, which...
September Patches for Azure DevOps Server
We are releasing new patches for our self‑hosted product, Azure DevOps Server. We strongly recommend that all customers stay up to date with the latest, most secure version of Azure DevOps Server. The most recent release, Azure DevOps Server, is available on the download page. The following versions have been patched. For more details on these updates, see the release notes: ⬇️Azure DevOps Server Patch Download ✅Verifying Installation To verify that the patch is installed, run the following command on the Azure DevOps Server machine using the patch installer you downloaded: Replace with the name of the...
Announcing Azure AI Speech LLM 2607: Better Multilingual Accuracy, Easier Customization
Learn how Azure AI Speech LLM 2607 improves multilingual and mixed-language recognition, lowers latency, and simplifies domain-specific customization with enhanced phrase lists.
Use C# unions and closed hierarchies in ASP.NET Core
Learn how C# unions and closed hierarchies work with System.Text.Json across ASP.NET Core Minimal APIs, MVC, SignalR, Blazor, and OpenAPI.
Why is the x86 undefined instruction called ud2? Why 2?
It came after <CODE>ud0</CODE> and <CODE>ud1</CODE>.
MSVC Build Tools Preview updates – September 2026
The MSVC Build Tools Preview is updated regularly with the latest features and fixes from the MSVC development team. This post covers updates from the past month, currently targeting the v14.52 release. This encompasses changes across the compiler frontend, backend, linker, standard library, and related tools. Although you can acquire the MSVC Build Tools Preview through either the Visual Studio 2026 Stable Channel or Insiders Channel, Insiders gets MSVC Preview updates more quickly (roughly weekly). To check whether it is installed, make sure one or both of these components are selected in the Visual Studio In...
What’s new in Microsoft Foundry: July and August 2026
Catch up on July and August in Microsoft Foundry: stable Hosted Agent and Toolbox SDK paths, Claude tools on Azure-hosted deployments, Model Router updates, local inference improvements, and the SDK migrations worth checking before you upgrade.
Advancing trusted AI innovation with Agents and new Azure OpenAI models in Azure Government
Today, we are announcing expanded AI capabilities available across the Microsoft Azure for US Government portfolio. The Microsoft Foundry Agent Service is now available in Azure Government, giving organizations managed infrastructure on which to build, deploy, and operate AI systems that can reason over authorized information, use approved tools, and help complete multi-step work. Additionally, GPT-5.6 Sol, GPT-5.6 Terra, and GPT-5.6 Luna are now available through Microsoft Foundry in Azure Government. Together, these capabilities give public-sector organizations more choice in how they build secure, scalable AI ...
What algorithm did Windows XP use to choose your initial user picture?
It's random, really.
Your work might not need the smartest model
The smartest model can cost five times more and deliver the same result, or even a worse one. See how evaluating your own work helps you get more value from your agent budget.
Announcing .NET 11 Release Candidate 1
.NET 11 Release Candidate 1 is available with improvements across libraries, runtime, SDK, MSBuild, NuGet, C#, F#, ASP.NET Core, .NET MAUI, and Windows Forms.
.NET Conf 2026 Community Days Call for Presenters Is Open
Submit your session proposal for the community-led .NET Conf 2026 Community Days by October 6, 2026.
.NET and .NET Framework September 2026 servicing releases updates
A recap of the latest servicing updates for .NET and .NET Framework for September 2026.
Go 1.27.1-2 Microsoft build now available
A new release of the Microsoft build of Go is now available for download.
MSIX PackageVolume: How Package Storage Works
An MSIX package can be staged in several ways and locations: By far the most common is PackageVolume. We'll dig into the rest in future posts, but for now let's focus on MSIX PackageVolume. In the beginning... When MSIX first appeared in Windows 81 packages would be staged to a unique directory under . More specifically, packages were placed in a subdirectory named with the package's full name. For example: Every package has a unique package full name, and thus is staged to a unique subdirectory within its package volume. This is commonly referred to as a pkgdir. This illustrates one of MSIX's ...
Today I will… find hidden latency across a distributed .NET application
When a distributed application feels slow, the user sees one delay. The code behind that delay may run across a web frontend, backend services, databases, and external APIs. If you profile only the frontend while the backend is slow, the profiler can show that the frontend is healthy without revealing the actual bottleneck. This article shows how to narrow a cross-process performance problem with Visual Studio: identify the process that owns the slow operation, capture its CPU activity, inspect the report, and add a focused measurement when CPU samples cannot explain elapsed time. GitHub Copilot Profiler Agent...
A sample use of the winstart.bat file in Windows 95
For a driver that needs high resolution mode only in Windows.
The Agentic Road to Revenue
The Agentic Road to Revenue From SaaS concept to Microsoft Marketplace. Building a SaaS application is only part of becoming a commercial software provider. To sell through the Microsoft Marketplace., the application also needs tenant isolation, subscription lifecycle management, billing integration, security evidence, and a publishable Partner Centre offer. To make this journey easier we have built SaaS_Skills into GIT-APE. This article follows Contoso Azure SaaS through seven stages, from selecting an offer model and applying the SaaS Architecture Reference Design to publishing its Azure ...
Why don’t we allow stacks to be sparse, instead of forcing them to be contiguous?
Imagining how to report a memory allocation failure for a sparse page.
Azure SDK Release (August 2026)
Azure SDK releases every month. In this post, you'll find this month's highlights and release notes.
What happens if you change a window class’s GCL_CBWNDEXTRA ?
You're changing the value for future windows.