I find it interesting for your example you chose Moment.js -- a time library instead of something utilitarian like Lodash. For years I've following Jon Skeet's blog about implementing his time library NodaTime (a port of JodaTime). There are a crazy number of edge cases and many unintuitive things about modeling time within a computer.

If I just wanted the equivalent of Lodash's _.intersection() method, I get it. The requirements are pretty straightforward and I can verify the LLM code & tests myself. One less dependency is great. But with time, I know I don't know enough to verify the LLM's output.

Similar to encryption libraries, it's a common recommendation to leave time-based code to developers who live and breathe those black boxes. I trust the community verify the correctness of those concepts, something I can't do myself with LLM output.