Every co-founder and CEO Dan Shipper published “How Codex Happened,” based on months of interviews with six Codex participants including Greg Brockman, Thibault Sottiaux and Alexander Embiricos. Chinese outlets including 机器之心, republished by 36Kr, and 量子位 summarized it. According to those accounts, Codex Cloud was built in about seven weeks and launched on May 16, 2025, but struggled externally because developers had to rebuild their environments in the cloud and the models were not yet capable enough. The team shifted to local work under Sottiaux, rewrote the agent core in Rust, and shipped a terminal CLI, editor sidebars and, on February 2, 2026, a macOS desktop app with no code editor. Every's figures, as cited by the outlets, put Codex above 5 million weekly active users in June; on July 9 the Codex desktop app became the new ChatGPT desktop app; Codex plus ChatGPT for Work are now above 40 million weekly actives. The report also says Sottiaux denied a decision to split out a Codex model line, describing it as an internal research exploration to speed its own work.