centurion/frontend/config-overrides.js

module.exports = {
    webpack: function (config, env) {
        return config;
    },
    devServer: function (configFunction) {
        // Return the replacement function for create-react-app to use to generate the Webpack
        // Development Server config. "configFunction" is the function that would normally have
        // been used to generate the Webpack Development server config - you can use it to create
        // a starting configuration to then modify instead of having to create a config from scratch.
        return function (proxy, allowedHost) {
            // Create the default config by calling configFunction with the proxy/allowedHost parameters
            const config = configFunction(proxy, allowedHost);

            config.proxy = {
                "/socket.io": {
                    target: "http://localhost:3001",
                    ws: true
                }
            }

            // Return your customised Webpack Development Server config.
            return config;
        };
    }
}