Is this repo maintained?

Which socket.io version does this supports?
Also, 
```js
manager.addReqHandler(
    async function(proxySocket, packet) {
        // Modify request here...
    }
);
manager.addReqHandler(
    async function(proxySocket, packet) {
        // Modify response here...
    }
);
```
`addReqHandler` is doing two job? Or you mean adding _Res_ Handler to act as a `response handler?`