[Bartkusa]

Hey, I'm a dev at Redfin, and I've done something like this (with Gigabo's help). It's possible, but it's not well-supported yet.

My team owns one special-snowflake API in React-Server. We want the API to be reachable from the client via HTTP, but also want to execute the code directly during server-side rendering, with no HTTP call. It's your exact use-case.

In order to do that, we

1. Detect if the API is invoked server-side.

2. Tell Superagent* to tell the client "hey, if you want data for $API_URL, don't make an HTTP request; the response will come inline in the page's HTML response.

3. Invoke the API code directly.

4. When the API response is ready, serialize it, and tell Superagent to pass it to the client.

We don't do this kind of thing frequently, so we haven't built any graceful tooling for it.

* I _think_ this is Superagent: https://visionmedia.github.io/superagent/https://visionmedia.... Somehow, we use it in a way that notifies the client of what HTTP requests the server is performing on its behalf; not sure if that's stock Superagent or if we added some magic to it.