Yes, you can use it for local coding. Most harnesses can be pointed at a local endpoint which provides an OpenAI compatible API, though I've had some trouble using recent versions of Codex with llama.cpp due to an API incompatibility (Codex uses the newer "responses" API, but in a way that llama.cpp hasn't fully supported).

I personally prefer Pi as I like the fact that it's minimalist and extensible. But some people just use Claude Code, some OpenCode, there are a ton of options out there and most of them can be used with local models.