Peter Steinberger, a research engineer at OpenAI, shared on May 23 that he has settled into a two-tool split: the Codex Mac app for knowledge work, learning, and reading, and cmux paired with Codex CLI for coding tasks. The post drew over 403,000 views and became the most-bookmarked AI story of the day with 2,900 saves. cmux, built by manaflow-ai, is a Ghostty-based terminal multiplexer designed to run multiple Codex CLI agents in parallel.
Community response was strongly positive, with 92% of sentiment-tracked replies praising the workflow. Developers noted the combination keeps context tight and purpose-separated across sessions. A minority flagged memory leaks and occasional lag. The thread also surfaced a broader shift in usage patterns: several engineers, including Chris Albon, said they now reach for the Codex Mac app over the ChatGPT app for day-to-day work.