Why is everyone quibbling with him about that. He just wants to express his opinion that the codebase is very bad in a more colorful way than by simply calling it doubleplusbad. Let's just take his word for it and move on.

Because we are trying to tell OP in a nice way something we think he will benefit a mot from rather than just what he seems to be wanting?

It's bad in a lot of specific ways but I'm trying not to out myself since it's a fairly small company.

The overarching problem is trying to reinvent the wheel because the management thinks we can do things better than the language designers.

The end result is a buggy and generally bad reimplementation of core libraries. ORM, math, dates, full text search. There's a half-baked custom version of everything.

Add regression tests, replace with your own code. or quit.

That's the worst thing to do: doesn't provide any value at the part that matters. It may worth to improve code quality where it matters (the business logic), but to improve it where it doesn't matter is a waste of time to both the employee and the employer

I would think this was implied:

Only noobs like myself years ago would go ahead and refactor a lot of code during work hours without a good reason.

However when you stumble through something and finally understand the idea behind it (good or bad) then it might be a good time to add a couple of tests.

And when you have a few tests that covers nearby code you can hopefully find the courage to make a few surgical cuts to remove the worst tumors. ;-)