Ruby on Rails on WebAssembly: A Full-Stack, In-Browser Journey

What if you could run a fully functional Rails application — backend, database, file storage, and all — directly inside a browser tab, with zero servers? WebAssembly (Wasm) makes this possible. By compiling Ruby and Rails into a Wasm module, the entire application stack executes client-side. This post explores a practical journey: from scaffolding your Rails app to shipping it as a Progressive Web App (PWA) that runs entirely offline. This article is an original write-up, providing a practical, technical deep-dive into running Ruby on Rails in the browser via WebAssembly. It was inspired by the following works:.