The dynamic module for Nginx (nwaf-dyn) is written in native C;
Nemesida AI modules (MLA, MLC) and Nemesida WAF Scanner are written in Python 3,
WUI modules (Cabinet, Signtest) are written in Python 3.
While using Nemesida WAF, the request processing time can increase by 0.05-0.1 milliseconds, because request'll process by signatures/ML, but the delay depends on the volume of a particular request (e.g if the request body is large, the processing time may increase).
In practice, the delay practically does not increase and the LA does not increase much (screenshot of a working server with the full version of Nemesida WAF).