He seems to have used the project as a conceptual experiment. In the "engine" folder's README, he mentions it's a work in progress but believes it might be usef

He seems to have used the project as a conceptual experiment. In the "engine" folder's README, he mentions it's a work in progress but believes it might be useful someday. I stumbled upon it while searching for a JavaScript state machine where one can define event pipelines triggered by rules or conditions applied to the state. I'd love to build web UIs using this approach in a performant manner.