Immutable approaches - macwright.com : vimarsana.com

Immutable approaches
These are some rough thoughts on how to do immutability in programming, to power undo. If you’re looking for an opinionated ‘this is how to do it’ sort of post, I’ve written that about Immutable.js. This is more a publicly-shared scratchpad.
For the fourth or so time in my career, I’m thinking about and implementing an ‘undo’ function. Undo is a powerful feature because it lets people do destructive or major operations without worrying because they can just hit command-z. Implementing undo is a subtle challenge for both UX & algorithms.
I don’t think that my standard approach, in-memory immutability, is the way to go anymore.