Seems pretty good, using the latest version of ollama (downloaded the default Q4 from ollama) and then popped it into Codex with this config.toml:

model = "qwen3-coder-next:Q4_K_M"
model_provider = "ollama"
model_reasoning_effort = "medium"

[model_providers.ollama]
name = "Ollama"
base_url = "http://localhost:11434/v1"

[analytics]
enabled = false

Works well in Codex CLI and VScode Codex IDE plugin. Did not work well with Kilo Code or Roo plugins unfortunately (but I have yet to find much that does).

I am not an expert, this may not be the best way, I don’t know… just sharing my experience for the other non-experts out there.