I wonder if WebAssembly could help accomplish that.
Still, even Rust has a compile-and-execute web service call accessible from the rust-lang home page. If Rust people (who tend to emphasize security) feel it is possible to secure that web service, then I'm inclined to believe them. It may be difficult though.
Actually I think the Rust folks would appreciate any feedback on the security of the service, as long as you don't DoS it or use it to do anything bad. :-)
Still, even Rust has a compile-and-execute web service call accessible from the rust-lang home page. If Rust people (who tend to emphasize security) feel it is possible to secure that web service, then I'm inclined to believe them. It may be difficult though.