AspNetCoreSpa is the first SPA library that was developed for ASP.NET Core and .NET Standard 2.0. The AspNetCoreSpa library is built in C#, which means it can be used with .NET Core and ASP.NET Core projects. We will need to create a new folder called AspNetCoreSpa in our project. It provides a unified interface to create rich, responsive single-page applications. Aspnet-core-react-template is a set of React components that are integrated into ASP.NET Core MVC projects. They provide an easy way to build modular, testable views in your apps using JSX and React.js syntax. Butterfly Server is a simple to use server framework built on top of WCF, Web API and ASP.NET Core that allows you to build high performance RESTful web services without writing a lot of code.