The LeasingNinja in Java as anemic big ball of mud.
If you haven't visited leasingninja.io yet, should do so now, as its the introduction to the further text.
THIS IMPLEMENTATION SHOWS ANTI-PATTERNS AND IS MEANT TO SCARE YOU OFF. IT'S AN EXAMPLE HOW NOT TO DO IT. DON'T USE THIS AS A BLUE PRINT FOR YOUR OWN ARCHITECTURE OR YOU WILL SEVERELY DAMAGE YOUR MENTAL HEALTH!