Working at a company that cared deeply about correctness and reading code over writing it was critical to my current coding style and beliefs. I've written about some of this at https://programsareproofs.com/articles/singleuse_functions.h..., but I developed an aversion to single-use functions, premature abstractions, and "self documenting" code. The code I write these days is drastically more understandable and modifiable than back when I targeted terseness, minimizing duplicated code, and future proofing.

As far as languages go, learning SML and functional programming was probably the biggest change for me.