Blacklist/whitelist per receiver domain / Promox Mail Gateway API

[onlime]

We are considering to employ Proxmox Mail Gateway in the near future. One major concern is the handling of blacklists/whitelists per receiver domain or even per single recipient:

• Is this possible through the mail filter rule configuration?
• Will the mail filter with hundreds or even several thousand rules (for each customer's domain) still perform well?
• Is there a way to setup mail filter rules in an automated way, preferably through an API (REST/SOAP)?
• Can we configure whitelisting to still add X-SPAM-headers (e.g. X-SPAM-LEVEL) and simply subtract e.g. 100 points of the level?

Or is Proxmox Mail Gateway simply not designed for such tasks and we would need to handle domain/recipient based black/whitelisting on our own mailserver? What would be the recommended way of doing this? Generating huge Sieve scripts, in my eyes, would not be the way to go.

Best regards,
Philip