Maybe-interesting contextual note: Daniel Peebles was one of the people involved at the beginning of iPhone jailbreaking.
Additional fun fact - the issue in question was not found during new development, but by just running the same code that had worked on previous macOS versions just fine. So besides a vulnerability, it's an user-visible regression to behaviour described by POSIX APIs.
Another if you know him: “He was just trying to make iOS more functional.”