rat's nest

noun2

1. •
   Something that is excessively complicated, entangled, or disorderly (either physically or metaphorically).

   • rat's nest of a wiring harness
2. •
   A software or hardware system whose design lacks organized structure, making it difficult to understand and maintain.

   • Think of libraries as the way the sub-idiots who like C code hide all the rat's-nest programming they don't want you to see.