### What?

This page is written in Markdown (actually in three Markdown files).

These Markdown files are requested by Fastly's Compute@Edge engine and rendered into
HTML at the edge, on every request.

You can check out the source code [here](https://git.nora.codes/nora/edgeblog).

The only dependency of the service, other than the Fastly SDK,
is Raph Levien's [`pulldown-cmark`][pulldown_cmark].
It's not an optimal choice, as it only supports one-shot rendering and requires buffering
the Markdown (though not the resulting HTML) in memory, but it's the best option available
at the moment.

[pulldown_cmark]: https://github.com/raphlinus/pulldown-cmark 

[![A diagram showing the difference in pipeline between normal websites with a CDN and this monstrosity](images/diagram.jpg)](images/diagram.html)

The renderer takes advantage of the fact that Markdown allows embedding raw HTML by embedding
anything with a "text" MIME type in the Markdown source, while passing through anything
without a "text" MIME type - images, binary data, and so forth - unchanged.

That allows the above JPG image to embed properly, while also allowing the linked SVG image page
to be rendered as a component of a Markdown document.


### Why?

I work on the Compute@Edge platform and wanted to get some hands on experience with it.
This is not a good use of the platform for various reasons; among other things,
it buffers all page content in memory for every request, which is ridiculous.

A static site generator like [Hugo][hugo] or [Zola][zola] is an objectively better choice
for bulk rendering, while the C@E layer is better for filtering, editing, and dynamic content.

[hugo]: https://gohugo.io/
[zola]: https://www.getzola.org/

That said, this does demonstrate some interesting properties of the C@E platform.
For instance, the source files are hosted in [a subdirectory][source] of my webserver;
in theory, you could directory-traverse your way into my blog source, but in fact,
you can't.

[source]: https://nora.codes/edgeblog/

I also have a [Clacks Overhead][clacks] set for my webserver, and the C@E platform
is set up to make passing through existing headers trivial even with entirely
synthetic responses like these, so that header is preserved.

[clacks]: https://xclacksoverhead.org/home/about