News

.NET 10 Release Candidate 1 Ships with Go-Live Support

• By David Ramel
• 09/16/2025

Microsoft announced the first release candidate of .NET 10 is now available with go-live support--ready for production apps. The company said this update brings enhancements across ASP.NET Core, Blazor, .NET MAUI, and EF Core, plus innovations like Post-Quantum Cryptography, Dark Mode in WinForms, and hybrid search in Cosmos DB. No new features were announced for the runtime, the SDK, C#, F#, Visual Basic, Windows Presentation Foundation (WPF) or container images.

To put RC1 through its paces, Microsoft recommends using the brand-new Visual Studio 2026 Insiders release. Visual Studio Code devs can try it out with the C# Dev Kit.

Go-Live Support
The go-live support license makes it supported for production use through Oct. 14, 2025. The announcement post states: ".NET 10 Release Candidate 1 is now available. This is our first of two release candidates which come with a go-live support license so you can confidently use this release for your production applications."

The go-live license was also a focus point for a livestreamed unboxing video where team members explores the issue in detail. "This is the first release candidate of .NET 10. That means we think we are pretty much done with this release, that this is a candidate we could just ship to you," said Daniel Roth, principal product manager for ASP.NET Core and Blazor, in an unboxing livestreamed video.

"Release candidate one. That means this thing's almost done. It's time to really start kicking the tires and taking it seriously," he added

For policy details on preview go-live support, see Microsoft's .NET support guidance here.

Tooling: Visual Studio and VS Code
As noted, Microsoft indicates RC1 is supported in the new Visual Studio 2026 Insiders; you can install that build via Visual Studio 2026 Insiders. Developers using VS Code can evaluate RC1 with the C# Dev Kit.

ASP.NET Core and Blazor
RC1 highlights for ASP.NET Core include persistent component state to improve navigation, new Identity metrics, validation improvements spanning Minimal APIs and Blazor, and OpenAPI schema generation improvements.

"In .NET 10, we're adding tons of capabilities to minimal APIs like improved open API support, support for server events, better JSON patch support using System.Text.Json, and of course the new validation support," Roth said.

Full technical notes are in the ASP.NET Core RC1 release notes on GitHub. The high-level overview for this release stream is in What's New in ASP.NET Core 10.0. In the announcement video, the team also discussed passkey sign-in support in ASP.NET Core Identity and broader validation scenarios.

Features such as identity improvements were also detailed in the unboxing video. "We've built in support for pass keys into the ASP.NET Core identity framework," said Mike Kistler, PM, ASP.NET Core. "If you build an app with ASP.NET Core identity, you now get pass keys just built right in."

.NET MAUI
For .NET MAUI, RC1 documents diagnostics and metrics updates, new HybridWebView events, a RefreshView.IsRefreshEnabled property, and experimental CoreCLR runtime support for .NET for Android.

"If you dive into the what's new in MAUI, for example, you're going to see all the goodies of all the stuff, the Aspire integration controls, the different web enhancements and performance improvements and all the stuff that's happened," said team member James Montemagno in the video.

See the MAUI RC1 notes on GitHub, plus the platform overview mentioned by Montemagno.

Libraries
The Libraries area emphasizes stabilization with notable updates such as post-quantum cryptography API completeness, UTF-8 hex string conversion helpers, and new tensor types (Tensor, TensorSpan, ReadOnlyTensorSpan). Details are in the Libraries RC1 notes on GitHub.

Windows Desktop
Windows Forms RC1 notes call out Dark Mode now fully integrated along with additional fixes and theming clarifications. Reference: the WinForms RC1 notes on GitHub and What's New in WinForms (.NET 10). For completeness, WPF is a quality-focused update in this RC; see What's New in WPF (.NET 10).

Entity Framework Core 10
EF Core 10 RC1 adds SQL Server vector search and JSON type support, plus Cosmos DB full-text and hybrid search (vector combined with full-text/RRF), complex types, and improvements for parameterized collections. The EF Core team also notes that, for RC1, JSON type support is temporarily disabled for Azure SQL Database and expected to be enabled by GA. See the EF Core RC1 notes on GitHub and the summary in What's New in EF Core 10.

What's New, Summarized

Getting Started
Install or update the .NET 10 SDK from the official download page here. For an overview of changes across the platform, see What's New in .NET 10 and the consolidated breaking changes list here.