What is deepcodex?

deepcodex is a macOS and Windows patch that lets a person run the official Codex Desktop app through DeepSeek's models instead of OpenAI's. Rather than rewriting Codex or building a separate editor, it keeps the existing Codex Desktop runtime, interface, and workflow in place, but adds a separate app icon, a separate entry point, and a local translator that converts requests into a format DeepSeek can understand. The README describes it as a patch, not a full replacement, and says the goal was to keep the change small and practical rather than build a new ecosystem. On first launch, a person enters their own DeepSeek API key, which is tested and saved automatically so it does not need to be re-entered. The tool supports running both the original Codex and deepcodex side by side. On macOS, this comes as a DMG file, on Windows, which is described as beta, it comes as a zip file with an installer script, and requires the official Codex Desktop for Windows to already be installed since the Windows package copies files from that existing install to build its own patched app. The compatibility layer covers most everyday coding tasks, including tool calls, cached context handling, and fallback versions of web search and web fetch. However, the README is explicit about limits: certain advanced capabilities, such as computer use, and connector style tools like Gmail, Google Drive, or Slack integrations, may still depend on OpenAI's own hosting and authorization, so they are not guaranteed to work through DeepSeek. Plugins and skills are shared with the regular Codex installation rather than reimplemented separately, though having a plugin installed does not always guarantee it is callable inside a DeepSeek session. The project is limited to personal, research, and non-commercial use. Commercial use, resale, hosted services, and paid integrations are explicitly not allowed.