svplot

Reusable Svelte 5 component for rendering Observable Plot charts.

Install

npm install @travishorn/svplot @observablehq/plot

@observablehq/plot is a peer dependency because you'll typically want to create marks and plot options with it.

Usage

<script>
	import * as Plot from '@observablehq/plot';
	import { ObservablePlot } from '@travishorn/svplot';

	let data = $state([
		{ category: 'East', value: 1 },
		{ category: 'North', value: 6 },
		{ category: 'South', value: 8 },
		{ category: 'West', value: 5 }
	]);

	let options = $derived({
		grid: true,
		marks: [
			Plot.barY(data, {
				x: 'category',
				y: 'value',
				fill: 'category'
			})
		]
	});
</script>

<ObservablePlot {options} />

When options changes, the component disposes the current plot and renders a new one. So if you wrap your data with $state() and your options with $derived(), as seen above, you can make the visualization "live."

For example, adding the following block will cause a random bar to change every 1 second. The rendered visualization updates when the data does.

setInterval(() => {
	const i = Math.floor(Math.random() * data.length); // Choose a random bar
	data[i] = { ...data[i], value: Math.random() * 10 }; // Set a random value
	data = [...data]; // Trigger reactivity
}, 1000);

API

ObservablePlot

Props:

• options: The plot options passed to Observable Plot, which are used to create the chart.
• Any additional attributes are forwarded to the div container element.

Development

Clone the repository:

git clone https://github.com/travishorn/svplot

Change into the directory:

cd svplot

Install dependencies:

npm install

src/lib contains the published library code. src/routes contains a demo app.

Run the development server:

npm run dev

You can see the demo in your browser at http://localhost:5173.

Check the types:

npm run check

Build and validate the package:

npm run prepack

Lint the code:

npm run lint

License

The MIT License

Copyright 2026 Travis horn

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.