The Weirdly Obscure Art of Streamed HTML

https://dev.to/tigt/the-weirdly-obscure-art-of-streamed-html-4gc2

Part 2 of an excellent series on rebuilding an ecommerce website to be as fast as humanly possible (while accepting mostly normal constraints)

mentions streaming HTML, which was not a technique I was familiar with and after reading the post I still don't thoroughly understand.

Mentions marko as a templating language that can make particular use of streaming:

Marko streams HTML with its <await> tag. I was pleasantly surprised at how easily it could optimize browser rendering, with all the control I wanted over HTTP, HTML, and JavaScript...

Imagine a component that displays recommended products. Fetching the recommendations is usually fast, but every once in a while, the API hiccups. <await>’s got your back:

<await(productRecommendations)
    timeout=50> <!-- wait up to 50ms -->
  <@then|recs|>
    <RecommendedProductList of=recs />
  </@then>

  <@catch>
    <!-- don’t render anything; no big deal if this fails -->
  </@catch>
</await>

then, you can add client-reorder:

The client-reorder attribute turns the <await> into an HTML fragment that doesn’t delay the rest of the page behind it, but asynchronously renders when ready. client-reorder requires JavaScript, so you can weigh the tradeoffs of using it vs. a timeout with no fallback. (I think you can even combine them.)

The best resource I can find on sending HTTP streaming requests in Go seems to be this stackoverflow post? Surely there must be better.