In the last piece I said the matching core had 56 tests. That sentence is close to meaningless, and I want to fix it here. Test count is not a quality signal. You can write a hundred tests that exercise every line and catch nothing, because they only ever ask the code to do what it already does. So when I wrote the suite for this thing, I wrote it the other way round: each test is a hypothesis that the gate can be beaten, and the test passes only when the gate goes red. The core is now pub...