OpenAI Rewrites Codex CLI in Rust for Enhanced Stability and Performance

Hello everyone! Thank you for the enthusiasm, valuable feedback, and contributions over the past month since the launch of Codex CLI. It’s been truly remarkable to see the community engage and build with both Codex CLI and Codex in ChatGPT. A special thanks goes out to all the contributors who have submitted pull requests to improve the CLI. Your efforts, whether it’s fixing bugs or adding new features, have made this project even more enjoyable to develop together. We’re excited to share updates on several key areas: cross-platform stability, security, performance, and extensibility. One significant change we’ve undertaken is rewriting Codex CLI in Rust. If you’re a TypeScript developer, you might be curious about this decision. The reason is simple: we want to use the best tools for the job. Although the current CLI offers a user-friendly terminal interface, built using React-based Ink, the core functionality involves calling the model repeatedly in a loop, which we refer to as an "agentic" harness. Our primary goals with the new Rust implementation are to enhance efficiency and address several areas of improvement: Cross-Platform Stability: Ensure consistent performance across different operating systems. Security: Enhance the overall security of the application. Performance: Optimize speed and resource usage. Extensibility: Make it easier to add new features and integrations. We will continue to merge bug fixes and improvements in the TypeScript version while we bring the Rust version up to speed in terms of features and user experience. Over the coming weeks, we’ll share more details about how TypeScript, Python, and other languages will fit into the long-term vision of this project. If you’re excited about working in Rust, contributing to codex-cli, and exploring new ways of agentic coding, we’re expanding our team and would love to hear from you. Reach out to us at codex-maintainers@openai.com. We’re eager to receive your feedback on the new Rust-based version of Codex CLI as we prepare to make it the default experience. Thank you for your continued support, and happy building!