Too Long; Didn't Read
Fat Lambda is an anti-pattern in which you group related code together in one or more files. Fat lambda uses internal routing to decide what code to execute based on the invocation event. The debate over whether to use a single-purpose function vs. a fat lambda continues to this day. Fat functions do not follow the [single responsibility principle] of the single responsibility principle. Instead of creating a single function that handles multiple responsibilities, we have the single purpose pattern where many functions do only one thing.