Kestrel Server in Dotnet
Kestrel is a cross-platform web server for ASP.NET Core. Kestrel is the recommended server for ASP.NET Core, and it's configured by default in ASP.NET Core project templates.
ASP.NET Core project templates use Kestrel by default when not hosted with IIS. In the following template-generated Program.cs, the WebApplication.CreateBuilder method calls UseKestrel internally:
var builder = WebApplication.CreateBuilder(args);