No way to delete keys from an Object

[luke-jr]

It seems they can only be added, never deleted?

[jgarzik]

Here's a first draft implementation on branch 2017_modify https://github.com/jgarzik/univalue/tree/2017_modify Needs improvement, comments welcome etc.

If merged, will there be downstream users?

[luke-jr]

I was looking to use it in Bitcoin Core a year ago. I don't recall why, but it probably won't be the last time.