Trouble hosting websocket server

let connections = [];

addEventListener("fetch", (event) => {
    event.respondWith(handleRequest(event.request));
});

async function handleRequest(request) {
    const upgradeHeader = request.headers.get("Upgrade");
    if (!upgradeHeader || upgradeHeader !== "websocket") {
        return new Response("Expected Upgrade: websocket", { status: 426 });
    }

    const webSocketPair = new WebSocketPair();
    const client = webSocketPair[0],
        server = webSocketPair[1];

    connections.push(server);

    server.addEventListener("message", (message) => {
        connections.forEach((connection) => {
            connection.send(message.data);
        });
    });

    server.addEventListener("close", () => {
        connections = connections.filter((conn) => conn !== server);
    });

    return new Response(null, {
        status: 101,
        webSocket: client,
    });
}