Long time no see!
In the original commenter's defense, I _did_ let the agents I have working on this get a more than a bit test harness crazy back when I was able to use GHC itself as a behavioral oracle. That worked fine through the initial build out, but then it rushed ahead with a broken CI due to misalignment in priorities, and then kept piling fixtures on top of fixtures and didn't properly track their cross-dependencies. My work on this in the last 48 hours has mostly been about getting that part under control and stable across my target platforms so I have better bedrock to build atop.