Solid (object-oriented design) - Wikipedia, the free encyclopedia

This is a "note-to-self". While mainly overlooked by many official computer science courses and graduations (mine included), Solid is a very important principle to apply to projects.

It should be standard practice to test every software implementation against it.

I'd turn it into a rule-of-thumb, if possible. After designing the domain classes, check for SOLID. After finishing every release of the product, check for SOLID. Nice and smart!