References serve nextJS in expressJS vercel/next.js#14532 https://github.com/vercel/next.js/blob/canary/examples/custom-server-express/server.js redirect 404 https://morioh.com/p/b6eda2ed88ae unique key https://stackoverflow.com/questions/28329382/understanding-unique-keys-for-array-children-in-react-js