This is an amazing talk discussing UI/UX (front-end) as well as back-end database schemas when it comes to personal profiling and building sane, logical forms to handle them.
For example, do you ask for date of birth, or age?
How should we approach non-binary gender fields?
Best practices for being inclusive of Latin or Chinese names
https://www.youtube.com/watch?v=PYYfVqtcWQY
A must-watch for any developer!