Okay, great! Thanks for your advice.
First of all i will use slim, but silex is also interesting.
I just use it for 6-8 little operations.
Okay, if there isn’t any tricky thing i try to install it 
Is it right, that i could install it via composer but also manuall or is it a step-by-step installation: first install composer, than manuall?
http://docs.slimframework.com/start/get-started/
How do i integrate it, do you got an tutorial?