Novel as in "an LLM can maintain coherence on a 100k+ LoC project written in zig"? Yeah, that's absolutely novel in this space. This wasn't possible 1 year ago. And this was fantasy 2.5 years ago when chatgpt launched.
Also impressive in that cc "drove" this from a simple prompt. Also impressive that cc can do stuff in this 1M+ (lots of js in the extensions folders?) repo. Lots of people claim LLMs are useless in high LoC repos. The fact that cc could navigate a "new" language and make "variables as emojis" work is again novel (i.e. couldn't be done 1 year ago) and impressive.