.NET 9 Release: New Framework for C# Explodes the Development Market

New framework for C# (.NET) is gaining popularity: what a developer needs to know

The .NET ecosystem continues to evolve rapidly. Following the release of .NET 8 and the announcement of .NET 9, the developer community has encountered a real breakthrough: a new framework built on modern features of C# 12 and 13 has begun winning the hearts of programmers worldwide. We are talking about FastEndpoints — a minimalist yet incredibly performant framework for building REST APIs.

Why FastEndpoints? Key features

FastEndpoints positions itself as a direct and faster alternative to the classic Minimal API and ASP.NET Core controllers. Its main goal is to speed up development without sacrificing performance. According to the latest benchmarks, the new framework shows up to a 30% increase in request processing speed compared to standard approaches.

• Minimalistic code: Instead of bulky controllers, a declarative approach is used. One endpoint — one class. This simplifies testing and code maintenance.
• Built-in validation: FastEndpoints integrates tightly with FluentValidation, allowing you to describe data validation rules directly inside the request handler.
• High speed: The framework uses native .NET capabilities and is optimized for working with System.Text.Json serialization, eliminating unnecessary overhead.
• Testability: Developers can easily create unit tests for each endpoint without needing to run a full web server.

What are developers saying?

On specialized forums and in the GitHub repository (already over 5 thousand stars), it is noted that FastEndpoints solves the problem of "spaghetti code" in large projects. "It's like Minimal API, but thought out to the smallest detail. I rewrote my old project to FastEndpoints in two days, and the performance increased by 25%," shares one Reddit user in the r/dotnet thread.

Furthermore, the framework actively supports the latest C# 13 features: primary constructors, ref struct, and collection expressions. This makes the code not only fast but also modern.

How to start using it?

For installation, just one NuGet command is enough:

dotnet add package FastEndpoints

After that, you can create your first endpoint in just a few lines:

public class MyEndpoint : Endpoint<MyRequest, MyResponse>{    public override void Configure()    {        Get("/api/hello");        AllowAnonymous();    }

    public override async Task HandleAsync(MyRequest req, CancellationToken ct)    {        await SendAsync(new MyResponse { Message = $"Hello, {req.Name}!" });    }}

Prospects and competitors

FastEndpoints is not the only newcomer. Its competitors include Ardalis.ApiEndpoints and RESTyard, but it is FastEndpoints that is showing explosive growth in popularity. According to Google Trends, interest in this framework has increased 4 times over the past six months.

With the release of .NET 9, which promises even greater performance (up to 50% faster JSON serialization), FastEndpoints could become the industry standard for building microservices and APIs. If you write in C# and haven't tried this framework yet, now is the time.

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