My company recently hired a contractor. He submits multi-thousand line PRs every day, far faster than I can review them. This would maybe be OK if I could trust his output, but I can't. When I ask him really basic questions about the system, he either doesn't know or he gets it wrong. This week, I asked for some simple scripts that would let someone load data in a a local or staging environment, so that the system could be tested in various configurations. He submitted a PR with 3800 lines of shell scripts. We do not have any significant shell scripts anywhere else in our codebase. I spent several hours reviewing it with him - maybe more time than he spent writing it. His PR had tons and tons of end-to-end tests of the system that didn't actually test anything - some said they were validating state, but passed if a get request returned a 200. There were a few tests that called a create API. The tests would pass if the API returned an ID of the created object. But they would ALSO pass if the test didn't return an ID. I was trying to be a good teacher, so I kept asking questions like "why did you make this decision", etc, to try to have a conversation about the design choices and it was very clear that he was just making up bullshit rationalizations - he hadn't made any decisions at all. There was one particularly nonsensical test suite - it said it was testing X but included API calls that had nothing to do with X. I was trying to figure out how he had come up with that, and then I realized - I had given him a Postman export with some example API requests, and in one of the API requests I had gotten lazy and modified the request to test something but hadn't modified the name in Postman. So the LLM had assumed that the request was related to the old name and used it when generating a test suite, even though these things had nothing to do with each other. He had probably never actually read the output so he had no idea that it made no sense.

When he was first hired, I asked him to refactor a core part of the system to improve code quality (get rid of previous LLM slop). He submitted a 2000+ line PR within a day or so. He's getting frustrated because I haven't reviewed it and he has other 2000+ line PRs waiting on review. I asked him some questions about how this part of the system was invoked and how it returned data to the rest of the system, and he couldn't answer. At that point I tried to explain why I am reluctant to let him commit his refactor of a core part of the system when he can't even explain the basic functionality of that component.