Ultra Street Fighter IV gets two rollback netcode mods made with Claude

Modders have created two separate projects attempting to replace Ultra Street Fighter IV’s older delay-based netcode with rollback netcode. Both mods were made using Claude.

Ultra Street Fighter IV was released in 2014 as the final version of Street Fighter IV. The original 2009 game is credited in the source with reviving the fighting game genre, while its community became known as “09ers.”

Delay-based and rollback netcode

Delay-based netcode responds to unstable connections by variably delaying players’ inputs. Rollback netcode accepts inputs immediately, then restores the game state when connection problems create inconsistencies between players.

The source says rollback became the industry standard for stability from the mid-2010s onward. Ultra Street Fighter IV retained delay-based netcode, which the modders are now attempting to replace.