Budget discipline the ad platforms do not enforce

Ad platforms are good at spending money and reporting on it. They are much less helpful at stopping. Daily budgets can be capped, but a monthly budget spread across many campaigns has no native hard stop.

In practice that leaves teams toggling budgets by hand, sometimes for an hour or two a day, to avoid an overrun.

Postlet's rules engine treats a group of campaigns as a single unit, evaluates it every hour, and pauses the group when the monthly budget is reached, with guardrails such as never pausing the last active ad.