Simon Willison released web-edit 0.1a0, a small Python web app providing a web UI for browsing and editing files in a folder, designed to run over Tailscale so he can securely edit files like credentials from his phone without round-tripping them through an LLM. The editor uses CodeMirror 6 and the app was built with Codex and GPT-6 Astra.
# Release: web-edit 0.1a0
Source: [https://simonwillison.net/2026/Oct/12/web-edit/](https://simonwillison.net/2026/Oct/12/web-edit/)
I was working on a project from my phone using Codex Remote when I found myself wanting to edit a credentials file without round\-tripping those credentials through the LLM itself\.
So\.\.\. I had Codex and GPT\-6 Astra Extra High build this Python web app which provides a web UI for viewing and editing files in a folder\. It's intended to be run over Tailscale, so I can have an agent start this running and then edit files via my Tailscale network directly from my phone\.
Here's the interface for browsing files in a folder:
Editing uses[CodeMirror 6](https://codemirror.net/)\- I was going to use[Monaco](https://microsoft.github.io/monaco-editor/)but that still doesn't have a great mobile experience yet\.
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