Kadal Deck

Kadal Deck

Write your talk in MDX. Present it in a browser. Let the room follow, vote and ask from their phones.

The tour, the engine's own feature deck: over a hundred slides, all written in MDX. Open it and press ?.

Get started · Docs · Live tour · Themes · Hosting · Changelog

Start in 30 seconds

You need Node 20.19 or later.

npm create @kadal/deck@latest my-talk
cd my-talk && npm install
npm run dev        # http://localhost:5173: edit deck.mdx and the slide you're on updates in place

A deck is one deck.mdx file: Markdown, split into slides at ---, with components when you need them.

---
title: Hello, room
theme: ocean
---

# Hello, room

---

## One point at a time

<Clicks>

- Slides split at `---`; a slide below this one starts at `----`
- Code steps line by line, and the notes follow your clicks

</Clicks>

---

<Poll id="lunch" question="Lunch?" options={["Dosa", "Biryani", "Both"]} />

When it's ready:

npx kadal-deck build      # dist/: a static site for any host, works offline
npx kadal-deck export     # PDF in export/ (add --png or --pptx)
npx kadal-deck publish    # a URL on deck.kadal.cc with a live room (free plan)

Already have a Slidev deck? npx kadal-deck import slidev slides.md converts it and writes a report of anything that didn't carry over.

What you get

The presenter view, and the audience's phone

Notes that highlight with each click, the next step, a timer with pacing and every tool on one screen. Press S in any deck. Scan the QR code: no app, no account. The slide stays in step with you, or roams ahead and catches up.

Themes

Sixteen themes, each in light and dark where it makes sense. Three are built in; the rest are packages you install and name in the headmatter (theme: ocean). Browse them all at deck.kadal.cc/themes.

minimal · built in

rla · built in

stack · built in ocean

brand crayon folio lecture

neon swiss terminal classic

seriph crisp bricks shibainu

Classic, seriph, crisp, bricks and shibainu are ports of the official Slidev themes, MIT-licensed, with credit to their authors in each package. npm create @kadal/deck@latest -- --theme <name> starts a theme of your own; the contract is THEMES.md.

For AI agents

Kadal Deck is built to be written by an agent as well as by you: a skill that teaches the format, an MCP server that edits slides line by line and renders them so the agent can look at its work, and a CLI whose every command answers in JSON. Guide: AI agents.

/plugin marketplace add kadalcc/deck          # Claude Code: the skill and the MCP server together
/plugin install kadal-deck@kadal-deck

npx skills add kadalcc/deck                              # the skill alone, for any agent (skills/kadal-deck)
claude mcp add kadal-deck -- npx -y @kadal/deck mcp      # the MCP server alone

For Claude Desktop, Cursor and VS Code, point the client at npx -y @kadal/deck mcp. The server works in the folder it starts in (or --dir <path>) and never reads or writes outside it unless started with --allow-outside.

For scripts: kadal-deck check (exit 1 on errors), kadal-deck screenshot, kadal-deck info [topic], and --json on every command. Exit codes: 0 ok, 1 failed, 2 usage, 3 not signed in, 4 missing prerequisite. @kadal/deck/catalog is everything a deck can use as data, @kadal/deck/authoring reads, lints and edits a deck as text, and @kadal/deck/schema/frontmatter.json is the JSON Schema for frontmatter.

In your editor

• VS Code extension (Marketplace): a live preview that follows your cursor, a slide outline you drag to reorder, IntelliSense for every setting and component, the deck's checks as problems, and formatting.
• @kadal/prettier-plugin: Prettier for deck files, in any editor that runs Prettier. kadal-deck format runs the same formatter with no setup.
• In the browser: press E in kadal-deck dev for a side editor on the slide you're on.

How it works

Each slide is its own module, so an edit re-renders one slide, not the deck. The drawing is an Excalidraw file, drawn with the same sketch DSL a slide's <Sketch> uses.

Hosted or self-hosted

Writing, presenting, the presenter view, export and a static build need nothing but this engine, and stay free. The live room needs a server holding a WebSocket per deck.

• deck.kadal.cc: npx kadal-deck publish gives the deck a URL, a live room, analytics, passcodes, version history and teams, and quick edit on the web that kadal-deck pull merges back into your files slide by slide. There is a free plan, and the paid plans fund the engine.
• Your own host: kadal-deck build output runs on any static host (kadal-deck ci writes the deploy files for GitHub Pages, Netlify, Vercel, Cloudflare or Docker). The room protocol is typed in @kadal/deck/protocol and documented endpoint by endpoint, and kadal-deck relay gives a static build the phone remote.

Packages

All @kadal/* packages version together and are published from this repository's release workflow through npm trusted publishing, with provenance on each npm page. The VS Code extension is published by its own workflow.

Documentation

Getting started · Writing slides · Components · Configuration · CLI · Publishing · Writing a theme · Coming from Slidev

The engine's full reference, with every component and option, is in packages/deck/README.md, and npx kadal-deck info prints it in the terminal.

Licence

AGPL-3.0-or-later. Presenting with Kadal Deck, self-hosting your own decks, and embedding a deck in a site you publish trigger nothing; you owe nobody anything. If you run a modified engine as a network service, its users must be able to get your modified source.

Building a hosted or proprietary product on the engine without publishing your changes? A commercial licence removes the AGPL obligations: write to hello@kadal.cc. Details are in LICENSING.md. The five ported themes are MIT, and third-party notices are in THIRD_PARTY_NOTICES.md.

Contributing

A bug report with a small deck.mdx that reproduces it is the most useful thing you can send, and pull requests are welcome. CONTRIBUTING.md covers the setup (Bun 1.3+), the tests and the island verifier. Questions and ideas go to Discussions. Please follow the code of conduct, and report security issues privately as SECURITY.md describes.

Sponsors

Sponsorships pay for time on the open-source engine: issues, docs, new islands and the features you ask for. Sponsor Kadal Deck on GitHub; the tiers and what each one gets are on deck.kadal.cc/sponsor, and backers are listed in BACKERS.md. Companies can sponsor by invoice.

Your logo here: be the first company to sponsor Kadal Deck.

Made in Chennai by Kadal · deck.kadal.cc · hello@kadal.cc