Slim-to-Core PHP Migration

I have a compact Slim-framework application—fewer than fifty source files and a lightweight database—that I now need running on plain Core PHP. The existing build already handles user authentication, several REST-style API endpoints, and standard PDO-based database connections; all three must survive the move exactly as they work today.

You’ll receive the current repository (Slim 4, Composer-managed) plus a SQL dump. Your task is to translate the routing, middleware, and helper layers into clean, well-structured Core PHP while keeping folder count and file size lean. I’m not looking for a full rewrite of logic; just strip away Slim’s dependencies and reproduce identical behaviour using vanilla PHP 8 syntax and built-in functions.

If you see opportunities for extra hardening, speed tweaks, or even a small utility class that could make maintenance easier, feel free to flag them—we can discuss those as optional add-ons later.

Deliverables
• Core PHP codebase that replicates current auth, API, and DB features
• Updated config/env files ready for deployment
• A short migration note explaining key architectural shifts and how to extend the project without Slim

I’ll spin up a staging server for testing the moment you push the converted code, so a quick turnaround and clear commit history will be appreciated.