Great question! While you could technically hack a similar behavior using a shell function (not a simple alias, as aliases don't handle positional arguments well), grsh implements mkcd as a native builtin. By baking it into the shell in Rust, I can ensure atomic execution and better error handling without relying on the user's specific .bashrc or .zshrc hacks. It's about providing a 'batteries-included' experience where common workflows are first-class citizens of the shell itself.