I have a set that’s harder to corrupt, but still not bulletproof:
Source of truth, system of record.
Business decisions should have a source of truth. But the domain of things we want to duplicate or not duplicate is bigger than just the business rules.
If you are asking two questions, it’s okay to have two implementations. If you ask the same question twice, you should get the same answer, not just the same output.
But miscreants can twist the meaning of five different parts of what I just said. Like what even is a business rule? It’s whatever the last thing they said before you got them to stop talking. But if they come back later and want something that disagrees with what they already asked, they’ll wriggle like a fish on a river bank trying to gyrate a way to interpret what they asked for to say you’re wrong (and therefore you should work nights and weekends and we don’t owe you a raise).
Source of truth, system of record.
Business decisions should have a source of truth. But the domain of things we want to duplicate or not duplicate is bigger than just the business rules.
If you are asking two questions, it’s okay to have two implementations. If you ask the same question twice, you should get the same answer, not just the same output.
But miscreants can twist the meaning of five different parts of what I just said. Like what even is a business rule? It’s whatever the last thing they said before you got them to stop talking. But if they come back later and want something that disagrees with what they already asked, they’ll wriggle like a fish on a river bank trying to gyrate a way to interpret what they asked for to say you’re wrong (and therefore you should work nights and weekends and we don’t owe you a raise).