Newer versions of Ultraviolet use bare-mux, a way to switch bare clients easily. To do this, you must pick a transport to install and use on your service. Some examples of ones are EpoxyTransport, CurlTransport, and Bare-Client.

Your files should be statically available from your web server. For this example EpoxyTransport will be hosted at /epoxy/ and bare-mux will be hosted at /baremux/

When using express, all transports and bare-mux provide a path that can be imported into your backend that hosts the static files. An example is shown below.

import { epoxyPath } from "@mercuryworkshop/epoxy-transport";
import { baremuxPath } from "@mercuryworkshop/bare-mux/node";

app.use("/epoxy/", express.static(epoxyPath));
app.use("/baremux/", express.static(baremuxPath));

This just provides the path and can be used with any other solution to host the files statically, like fastify.

The newest version of bare-mux uses SharedWorkers. To initialize bare-mux we have to start a connection. The connection takes the worker path in as a required argument that is needed to proceed with the connection. The

import { BareMuxConnection } from "@mercuryworkshop/bare-mux"
let connection = new BareMuxConnection("/baremux/worker.js")

Without using a bundler:

let connection = new BareMux.BareMuxConnection("/baremux/worker.js")

After your connection is setup, you can call connection.setTransport to change your transport. The first argument is required and the path to the module version of your transport. For most of them it should be /path/to/transport/index.mjs, otherwise it should be checked. The second required path is an array that gets interpreted as arguments.

await connection.setTransport("/epoxy/index.mjs", [{ wisp: "wss:https://wisp.mercurywork.shop/" }]);
await connection.setTransport("/baremod/index.mjs", ["https://tomp.app/"]);

It is recommended to keep your UltraViolet page in an IFrame of the page with the initialized connection, as sometimes the service worker loses connection and needs to contact the page to get a MessagePort back. If your enviroment is not setup like this, it may cause issues.

Your transport should get set before the service worker is ready, otherwise this may cause a race condition and the transport may not be used for some requests.

If you are moving from bare-mux v1, you can remove your imports of the transportss in the page and service worker as bare-mux v2 streamlines the experience to where imports are loaded inside of the SharedWorker. The only time where bare-mux needs to be imported now is when you are making the connection with BareMuxConnection.