New framework for C# (.NET) gains popularity among developers

New framework for C# (.NET) gains popularity: what developers need to know

The .NET ecosystem continues to actively evolve, and a new player has appeared on the horizon that is rapidly gaining momentum. We are talking about the FastEndpoints framework — a lightweight alternative to the traditional ASP.NET Core Minimal API. Over the past few months, its installation count via NuGet has grown by 400%, and the developer community is actively discussing its advantages in blogs and at conferences.

FastEndpoints is created for those who want to write clean, high-performance code without unnecessary magic. Unlike controllers, where each endpoint often requires a separate class with attributes, FastEndpoints offers a more concise approach — one file = one endpoint. This simplifies maintenance and testing.

Key features of FastEndpoints

• Maximum performance: the framework is only slightly slower than minimal APIs but significantly outperforms standard ASP.NET Core controllers (up to 30% faster).
• Built-in validation: supports FluentValidation out of the box, eliminating the need to write checks manually.
• Simple error handling: a unified mechanism for returning errors, including custom codes and messages.
• Swagger/OpenAPI support: documentation is generated automatically, without additional configuration.
• No magic: transparent code that is easy to read and debug.

Code example: what an endpoint looks like

Here is a simple example of an endpoint for user registration:

public class CreateUserEndpoint : Endpoint<CreateUserRequest, UserResponse>{    public override void Configure()    {        Post("/api/users");        AllowAnonymous();    }

    public override async Task HandleAsync(CreateUserRequest req, CancellationToken ct)    {        var user = new User { Email = req.Email, Name = req.Name };        // Saving logic        await SendAsync(new UserResponse { Id = user.Id }, StatusCodes.Status201Created);    }}

As you can see, minimal boilerplate code — all logic is concentrated in one place.

Why is FastEndpoints gaining popularity?

The main reasons are simplicity and speed. Unlike heavyweight solutions such as MediatR or CQRS, FastEndpoints does not require a mountain of abstractions. It is ideal for microservices, startups, and projects where fast iteration is important. Additionally, the framework is actively maintained: regular updates, over 50 contributors on GitHub, and 10,000+ stars.

Many developers note that after switching to FastEndpoints, the development time for new endpoints is reduced by 20–30%, and the number of bugs decreases due to built-in validation.

Disadvantages to consider

• Relatively young project (first release in 2022) — the community is smaller than that of ASP.NET Core.
• Not suitable for monolithic applications with hundreds of endpoints — may require more files.
• Fewer educational materials in Russian.

Prospects and conclusions

FastEndpoints is not just a "trendy toy" but a real tool already used in production by companies such as JetBrains and Stripe. If you work with .NET and are looking for a balance between performance and convenience, it is worth taking a closer look at this framework.