I’ve used them in production several times, recently when I needed to quickly check to see if a set of numbers were likely all the IDs of a particular kind of o

I’ve used them in production several times, recently when I needed to quickly check to see if a set of numbers were likely all the IDs of a particular kind of object, where the ID space is 64-bit ints and the population is in the hundreds of millions. We didn’t need perfection, just a bound error rate and predictable memory consumption, and a pre-loaded BF was perfect in this role.