Lectern

Lectern — a visual editor for slides your AI assistant writes

**Ask Claude, ChatGPT, Copilot or any coding agent for a presentation, then move things around yourself.** Lectern is a drag-and-drop editor for HTML slide decks: the assistant writes the file, you fix the layout on a canvas, and each of you sees the other's changes within a second.

npx lectern-editor new my-talk --title "Why whales lost their legs"   # scaffold a deck
npx lectern-editor my-talk/index.html                                 # open the editor

**The `.html` file is the deck** — a [reveal.js](https://revealjs.com) presentation. There is no proprietary format, no import and no export step: it opens in any browser, prints to PDF, and lives in git like any other file. Lectern writes back only the slides you changed, byte for byte, so `git diff` stays readable and your assistant can keep editing the same file while you have it open.

• Nothing leaves your machine. No account, no telemetry, no hosted version, no runtime dependencies. Works with the wifi off — the tests fail if any part of the editor so much as tries to reach the network.
• One file, no install: double-click Lectern.html (a single self-contained page, from file://). Or npx lectern-editor for Firefox and Safari, which have no folder picker.
• Works on decks you already have, and on any hand-rolled page of slides.
• Five-minute tutorial: public/tutorial.html (the editor's Help menu opens it).

*Made for people who like the slides an LLM writes but not the layout it leaves behind: a PowerPoint- or Keynote-shaped canvas over plain HTML, with the assistant still in the loop.*

Slides with an AI

Ask your assistant for a deck; it writes an HTML file. Open that file in Lectern and fix the layout by hand while the assistant keeps working on the content. Where you want something changed, press **`N`** on the slide and write it there — *"draw a whale here"*, *"this is too dense, spl