I’d rather rewrite the entire app from scratch ..however complex.... than modify existing code..

Go for it

Greenfield is more enjoyable in most every case, agreed.

My app is currently also in a total mess. Here’s the weirdest thing:

I had to write some multi-threaded code. I wanted to decrypt a file while showing a nice animated loading screen. IT WORKED IN THE FUCKING EMULATOR AND NOT ON MY ACTUAL PHONE WTH

Refactoring isn't a good solution at all.

Writing from scratch is always worth a try - since brain can better understand what's happening and why, discovering new solutions and better approaches.

Greenfield is fun - look for jobs that mention it specifically. Made an effort to switch to Greenfield in my last role change and damn it was worth it - a modern AWS kubernetes stack with Java 11+ and beautifully written code.

That being said, you won't be able to (most likely) do that for your entire career - working with crappy codebases, without rewriting them, is unfortunately a necessary skill to develop in this industry.

Greenfield is fun until something is far beyond your experience (and scale) and you don't know where to start and basically rewrite it at least two times. Actually that's still mostly fun if your manager has your back and gives you the needed time.

P.s.: I'm referencing a solo project that took me far more than 1 year (mostly full time) when I was quite green and was rewritten by myself twice. Certainly a good learning experience, but I burned a lot of time recreating the wheel.

existing code written by someone else*