When building an HTTP server in TypeScript, I encountered an issue where the `RateLimiter` class was imported before it was declared in the same file

When building an HTTP server in TypeScript, I encountered an issue where the RateLimiter class was imported before it was declared in the same file. This violates TypeScript's module resolution rules, leading to a compilation error. The problem arises because TypeScript processes files top-to-bottom, and referencing a class before its declaration results in it being undefined at runtime. The correct approach is to ensure all class declarations are defined before they are used, either by reordering the code or moving the import statement after the class definition.