Thanks for the comparison! I had been looking at adding diagnostics to a tool I’m working on (https://discuss.ocaml.org/t/ocaml-is-awesome/13700). So Asai uses algebraic effects, which I can’t use because I’m stuck on OCaml 4 (and I need Windows). I tried installing Grace but as you mentioned it depends on core … the problematic dependency for me at the moment is core_unix which is not available on Windows.
I will take a look at Grace (not now though) to see how tightly coupled it is to core_unix.
Thanks for releasing the project!