Codex bundles LibreOffice

<p>I was poking around in my <code>~/.cache/</code> folder using <a href="https://www.omnigroup.com/more">OmniDiskSweeper</a> when I spotted something interesting. The OpenAI Codex desktop app (since <a href="https://help.openai.com/en/articles/20001276-moving-to-the-new-chatgpt-desktop-app">rebranded</a> to just ChatGPT) has 1.7GB of stuff in there in a folder called <code>codex-primary-runtime</code>, including a full Python installation, a full Node.js installation, and native binaries for <a href="https://poppler.freedesktop.org">Poppler</a>, git, and the <a href="https://en.wikipedia.org/wiki/LibreOffice">LibreOffice</a> open source office suite (which forked from OpenOffice.org in 2010):</p> <p><img alt="Screenshot of a macOS disk usage app window in column view, titled &quot;/Users/simon/.cache - 442.1 GB&quot;. First column: 356.8 GB huggingface, 82.5 GB uv, 1.7 GB codex-runtimes (selected), 609.0 MB datasette-sqlite, 298.8 MB rod. Second column: 1.7 GB codex-primary-runtime (selected). Third column: 1.7 GB dependencies (selected), 6.3 MB plugins, 4.1 kB runtime.json. Fourth column: 771.0 MB native (selected), 446.4 MB node, 440.6 MB python, 28.7 kB bin. Fifth column: 429.7 MB libreoffice-headless (selected), 187.9 MB poppler, 148.1 MB git, 4.7 MB libheif, 679.9 kB jxrlib." src="https://static.simonwillison.net/static/2026/codex-primay-runtime.webp" /></p> <p>The <code>~/.cache/codex-runtimes/codex-primary-runtime/plugins/openai-primary-runtime/plugins/documents</code> folder includes skills which tell Codex how to find and use those binaries.</p> <p>Tags: <a href="https://simonwillison.net/tags/codex">codex</a>, <a href="https://simonwillison.net/tags/generative-ai">generative-ai</a>, <a href="https://simonwillison.net/tags/openai">openai</a>, <a href="https://simonwillison.net/tags/ai">ai</a>, <a href="https://simonwillison.net/tags/llms">llms</a>, <a href="https://simonwillison.net/tags/openoffice">openoffice</a>, <a href="https://simonwillison.net/tags/open-source">open-source</a></p>