> Also choose a statically typed language, so that your function signatures will give you a useful contract to work with, and it will mostly be pretty easy to t

> Also choose a statically typed language, so that your function signatures will give you a useful contract to work with, and it will mostly be pretty easy to trace the intent of your code. Furthering this, avoid: - "Stringly typed programming": where everything has a static type, but they're all `String` (or `Int`, `Float`, etc. instead of something with domain meaning). This gives very little information to the reader, and makes it easy to mix-up values. - "Boolean blindness": where we query a bunch of booleans to determine what data we can extract, e.g. Result::hasUserId : Boolean Whether this result contains a UserId Result::getUserId : UserId Returns a UserID if hasUserId; otherwise error log("Request came from " + myResult.hasUserId? myResult.getUserId : "anonymous guest") Compare this to e.g. Result::getUserId : Option[UserId] log("Request came from " + myResult.getUserId.orElse("anonymous guest"))