I think he means if you want to offer React server side you will need some-sort ...

makeee · on Oct 27, 2020

Next.js does server-rendering and has API routes built-in. No need for Express or Fastify unless you like the DX of those frameworks better.

jayflux · on Oct 28, 2020

The Parent parent was talking about if you don’t use Next and want a more sophisticated setup then then those are alternatives.

The parent then asked why do you need to integrate [react] with Express and my answer was if you want to do server side (not using Next)

randomchars · on Oct 28, 2020

React was not even mentioned in the thread. OP mentioned integration Next with Express, not React.

Using Express and Next together is relatively common (or at least used to be): https://github.com/shdnx/next-express