Licensing

The engine: AGPL-3.0-or-later

@kadal/deck and every @kadal/deck-* package are free software under the GNU Affero General Public License, version 3 or later. You may use them, change them and build on them, for anything, including commercially.

The one obligation that matters in practice: if you run a modified version of the engine as a network service, the people using that service must be able to get your modified source. That is AGPL §13, and it is why this licence was chosen over MIT. Running an unmodified copy, embedding the engine in a site you publish, or presenting with it triggers nothing.

If you are self-hosting your own decks, the AGPL is all you need, and you owe nobody anything.

Commercial licence

If you want to build a hosted or proprietary product on top of the engine without publishing your own source, a commercial licence removes the AGPL obligations. That arrangement funds the engine’s development, in the same way Slides.com funds reveal.js. Ask: pmithunish@gmail.com.

Why the split

The engine is the part that should belong to everyone: the compiler, the runtime, the components, the themes, export and the framework renderers. A deck you wrote should keep rendering with no account, no network and no company, for as long as a browser exists.

The parts that cost money to run — the live room, publishing, accounts, analytics — are the product. That boundary is honest about where the expense is: a room holding a hall of phones is somebody’s bill.

Contributing

Contributions to the repository are accepted under the AGPL, and because the engine is dual-licensed, they may also appear in the commercial offering. A contributor licence agreement will be in place before outside contributions are merged.

The hosted service

deck.kadal.cc is a paid service, separate from the engine’s licence. Its use is governed by the terms of service, privacy policy and refund policy.