It's not a bad idea to strongly type the username and password so that you can't so easily pass in unexpected input to the login / can centralize validation (e.

It's not a bad idea to strongly type the username and password so that you can't so easily pass in unexpected input to the login / can centralize validation (e.g. username and password can't be more than 100 bytes each to attempt a login). It also lets you implement things like secure erasure of the password once it gets dropped. Weakly typing that though is a sin. I wish Rust made creating strongly typed wrappers around primitives a bit more ergonomic.