Today, nearly all browser-based apps are written in JavaScript (or similar languages that transpile to it). That’s fine, but there’s no good reason to limit our industry to basically one language when so many powerful and mature alternate languages and programming platforms exist. Starting now, WebAssembly opens the floodgates to new choices, and one of the first realistic options may be .NET. Blazor is a new experimental web UI framework from the ASP.NET team that aims to bring .NET applications into all browsers (including mobile) via WebAssembly. It allows you to build true full-stack .NET applications, sharing code across server and client, with no need for transpilation or plugins. In this talk, I’ll demonstrate what you can do with Blazor today and how it works on the underlying WebAssembly runtime behind the scenes. You’ll see its modern, component-based architecture (inspired by modern SPA frameworks) at work as we use it to build a responsive client-side UI. I’ll cover both basic and advanced scenarios using Blazor’s components, router, DI system, JavaScript interop, and more.