This is an online C# compiler that runs directly in your browser. So, your code won't be sent to a backend server to be compiled. This is achieved by utilizing Blazor WASM(WebAssembly), which allows us to make and run C# apps(including the Roslyn compiler APIs) in a browser.
I decided to use GUN.js(decentralized graph database) to store the data and live share the code editor.
The account and its data are saved to the GUN.js decentralized database. Warning: I'm not hosting a relay node, so any data you save is reliant on public nodes, which may not store your data indefinitely. You can add additional nodes under: Gun Nodes
You can try it out here