This is an opensta/openroad command.

That feature deserves an announcement!

Yes, it needs some more testing.

We've been using it on Microwatt, creating liberty files for 6 macros including 3 DFFRAMs and passing all of them into a top level integration. Seems to be driving the resizer correctly, and a hierarchical STA of everything is clean.

The thing to watch out for is delay calc accuracy if there is a long wire in the block and also constraint accuracy which can have a severe error if there are multiple clocks or timing exceptions in the block. None of the constraint part or complex parasitic handling has been done.