Alas, I've been working on something like this for the last few weeks on and off, especially the "patching" of immutable data, my solution was to use jiff[1], which generates JSON Patch operations[2], which is then applied to the Immutable object using immpatch[3] (a lib I wrote).

A cursory look at Remutable seems it to be the better and faster option :)

[1] https://github.com/cujojs/jiff

[2] https://tools.ietf.org/html/rfc6902

[3] https://github.com/zaim/immpatch

(edited formatting)