Details on pre-rendering with AMP HTML

Question

I've seen some mention of pre-rendering with AMP pages. Specifically, the project's how-it-works page (https://www.ampproject.org/how-it-works/) says:

AMP documents are from the ground up designed to be efficiently pre-renderable. Browsers have long supported pre-rendering through the <link rel=prerender> tag, but they need to be conservative about this mechanism because prerendering can be expensive. With AMP HTML we added the ability to tell a document: render yourself, but only as far as what is visible above the fold and only elements which are not CPU intensive to minimize the cost of pre-rendering.

I'd like to understand more about how the pre-rendering works:

• Is there any further documentation on this pre-rendering? I haven't been able to find any further details.
• Where is the code that implements the pre-rendering?
• If it's not a link with rel=prerender, what's the technique used for pre-rendering?
• How do you indicate to an AMP html page to render in pre-render mode where it only loads above the fold resources, etc.. ?
• Is there some nicely packaged way for someone to use this pre-rendering on their own AMP site (when navigating between pages)?

Answer 1

I wrote about how prerendering works in AMP in this post.

We do not yet have great docs on how to use this, but it is one of our goals for this year to provide stable SDKs for web, iOS and Android that has prerendering builtin.