How to correctly set onReady for TransformNode creation?

I’m trying to invoke the onReady property by setting it to a function.
I can’t seem to get it to be called though, and I’m not sure how to get the property to be called correctly by reading the documentation (TransformNode | Babylon.js Documentation).

I don’t see an option to set it in the constructor…

Setting the property after creation of the transform node doesn’t seem to do anything:

What am I missing?

In fact, this observable is triggered only as part of TextureDome and GroundBuilder work, it is not used to notify of some internal changes of TransformNode / Node.

Ok thanks for clarifying, I’ll have to use something else for my use case then.