Rules to live by

"Complaining don't fix things,
Blaming just causes more trouble,
We are trying to get things done here,
If you can't help, at least get out of the way."

"You're not able to tell me if that's easy or not,
you're not able to tell me if that's fast to make of not.
Unless you are the one who will do it."

"I don't care about the best way. I need a good way that works."

"Double things to do, double time. Triple things, triple time. That's basic arithmetic, right?"

"If you can't put it in numbers, you don't really know about it"

And the basic principles for any developer: K.I.S.S. and D.R.Y. (I would also add "C.O.C." - Conventions over Configurations, but that's a nice thing to have, not a must one)