Slitherine

I'm not sure if it's a bug.

I've never seen a "builder guild" full stop.

The same is true for tar deposit.
Requirement matched, but they are not even in the available structures list.

I have seen tar workshop. Its rare though. I have never seen synagoge/holy estate.

I've seen tar workshop too, but it is very rare.

Tar deposit is tricky to pull out, you must be in a swamp and have done the 'swamp draining' building.

Builder Guild is a tier III infra, nothing special. If you are sure you meet the conditions for any building and don't see it in the list:

Send the file(s) to support@slitherine.co.uk, copy-paste the thread URL and title and mention this is for Pocus please.

Plenty tiers 3 building . Extra infrastructure but drain a bit manpower.