How to use with pkg

The client files are not automatically included as assets, you need to manually specify them:

index.js

const { Server } = require("socket.io");
const io = new Server();
io.on("connection", (socket) => {  // ...});
io.listen(3000);

pkg.json

{  "assets": "node_modules/socket.io/client-dist/*.js"}

And then run:

$ pkg -c pkg.json -t node14-linux index.js

And voilà!