examples/cms-sitecore-xmcloud/src/lib/site-resolver/plugins/default.ts

import { SiteInfo } from "@sitecore-jss/sitecore-jss-nextjs/middleware";
import config from "temp/config";
import { SiteResolverPlugin } from "..";

class DefaultPlugin implements SiteResolverPlugin {
  exec(sites: SiteInfo[]): SiteInfo[] {
    // Add default/configured site
    sites.unshift({
      name: config.jssAppName,
      language: config.defaultLanguage,
      hostName: "*",
    });

    return sites;
  }
}

export const defaultPlugin = new DefaultPlugin();