OpenAI had been looking to get a foot int the door in the AI coding space by acquiring a company like Cursor or Windsurf, but it might’ve created a popular in-house coding tool by itself.
OpenAI CEO Sam Altman has said that Codex, OpenAI’s cloud-based software engineering agent, had seen its usage rise 10x in the last two weeks. “Really cool to see how much people are loving Codex, usage is up ~10x in the past two weeks!” he posted on X. “Lots more improvements to come, but already the momentum is so impressive,” he added.
Codex is a cloud-based software engineering agent that can work on many tasks in parallel. Codex can perform tasks such as writing features, answering questions about the codebase, fixing bugs, and proposing pull requests for review. Each task runs in its own cloud sandbox environment, preloaded with the user’s repository. Codex is powered by codex-1, a version of OpenAI’s o3 optimized for software engineering.
Coding is one of the fastest-growing use cases in AI. There are coding IDEs like Cursor and Windsurf, that help programmers write their code. Then there are tools like Loveable, which help non-coders create functional apps. Then there are tools like Claude Code, Codex and Google Jules, which have complex code understanding and terminal and command-line task execution, and show higher accuracy on some software engineering benchmarks.
Claude Code has been Anthropic’s latest hit. Launched in February this year, it already has an annual run-rate of $500 million. Even within the company, the model has seen plenty of adoption, and 80% of Claude Code’s code is now written by Claude Code itself. OpenAI now seems to have created a competitor in Codex which is generating a lot of buzz. And if these trends continue, OpenAI might have another hit on its hands after the massive success of ChatGPT.