I created a simple svelte-sigma app like this:
npm init vite svelte-sigma -- --template svelte
cd my-app
npm install
npm run dev
after I installed sigma.js:
npm install graphology sigma
Now I changed App.svelte like this:
App.svelte
<script>
import Sigma from 'sigma';
import Graph from 'graphology';
import { onMount } from 'svelte';
onMount(() => {
const container1 = document.getElementById("sigma-container");
const graph = new Graph();
graph.addNode("John", { x: 0, y: 10, size: 15, label: "John", color: "blue" });
graph.addNode("Mary", { x: 10, y: 0, size: 10, label: "Mary", color: "green" });
graph.addNode("Thomas", { x: 7, y: 9, size: 20, label: "Thomas", color: "red" });
graph.addNode("Hannah", { x: -7, y: -6, size: 25, label: "Hannah", color: "teal" });
graph.addEdge("John", "Mary");
graph.addEdge("John", "Thomas");
graph.addEdge("John", "Hannah");
graph.addEdge("Hannah", "Thomas");
graph.addEdge("Hannah", "Mary");
const renderer = new Sigma(graph, container1);
});
</script>
<h1> Sigma graph exemple</h1>
<div id="sigma-container" />
<style>
#sigma-container {
width: 550px;
height: 450px;
}
</style>
and I have this render on my localhost:

You can see this exemple