How to Connect Codex to DeepSeek, Qwen and Other Third‑Party Models in Minutes

CC Switch is a free, open‑source cross‑platform desktop tool that intercepts Codex requests locally and forwards them to a user‑specified API provider, making model switching transparent to Codex.

Working principle

CC Switch runs a lightweight proxy on the machine. When Codex sends a request, the flow is:

Codex → CC Switch → DeepSeek/Qwen/GLM → CC Switch → Codex

The proxy rewrites the request so Codex still thinks it is calling the official OpenAI endpoint, while the actual backend can be any compatible model.

Prerequisites

Codex installed

DeepSeek API key (obtain from DeepSeek portal)

Operating system: Windows 10+, macOS 12+, or mainstream Linux distributions

CC Switch v3.16.0 or newer

Step 1 – Install CC Switch

Download the latest release from https://github.com/farion1231/cc-switch/releases/latest. Choose the package for your OS:

Ubuntu/Debian: sudo dpkg -i CC-Switch-*.deb or sudo apt install ./CC-Switch-*.deb Fedora/RHEL/CentOS: sudo rpm -i CC-Switch-*.rpm or sudo dnf install ./CC-Switch-*.rpm openSUSE: sudo zypper install ./CC-Switch-*.rpm Arch/Manjaro: download the .AppImage, make it executable ( chmod +x CC-Switch-*.AppImage) and run, or install via AUR.

macOS (recommended): install the notarized version via Homebrew: brew install --cask cc-switch Windows: download the .msi from GitHub Releases and run the installer.

Step 2 – Add DeepSeek as a provider

Open CC Switch and select the "Codex" application in the top switch bar.

Click "+ Add Provider" in the left "Providers" pane.

Search for "DeepSeek" in the preset list and choose the desired preset (v3.16.0 includes DeepSeek V4 flash and pro).

Enter your DeepSeek API key in the form; keep other fields at their default values.

Enable local routing and click "Save".

Step 3 – Enable routing

When you switch to the DeepSeek model, CC Switch prompts to enable routing. Open the settings menu (gear icon) and turn on routing, then select Codex as the target application.

After restarting Codex, the DeepSeek model badge appears, confirming that requests are now routed through the third‑party model.

By following these steps, users can keep the familiar Codex interface while freely choosing among multiple large‑model backends and significantly lowering API usage costs.