I've been working in Zed, using Claude 3.5 Sonnet. For completions, it's fine. No real complaints.
But when I try to do something larger (>200 LOC), I'm finding the output is often very bad. (Doesn't matter the language.)
It's likely that I'm not able to express in a short block of text what I'm trying to accomplish. So the small text prompt approach is likely the wrong UI.
The C preprocessor comes to mind, it's good I think. You can also use C++ templates recursively to generate lots and lots of code, which I guess can be good in some cases if you know what you are doing.