Does it strictly HAVE to be vanilla Mari0 or can we Speedrun with other versions like Alesan 99's Entities?

I ask because I'd like to speed run using Chell Alt from this thread as well as take on other mappacks.

iirc from running both (granted like 6 years ago) the physics are different in Alesean. I think it was something like gaining momentum through portals unlike in vanilla.

If you want to run Alesan there is an Alesan board.

You are allowed to use the Speedrun Tool which enables FPS limiting and autosplitter, but I think so far that is the only allowed mod.