3rd way to detect changes?

[Coffee2JS]

In the docs it says:

As seen in the previous snapshots section, any change made to a tree node will generate a new snapshot, but this is only one of the three possible ways mobx-keystone offers to detect changes. The second way is "patches".

What's the 3rd way?

And, kudos for good work, this is a great library 👍

[xaviergonz]

I guess the third one would be mobx reactions :)