serve: Rewrite of the Server-Sent Event code for build notifications. At the moment the server monitors the asset directories, and notifies the browser when an asset has changed and has been re-processed. * Fix issues around long-running requests/threads which mess up the ability to shutdown the server correctly with `CTRL-C` (see comments in code). * Move the notification queue to each SSE producer, to support having multiple pages open in a browser. * Add JS/CSS for showing quick notifications about re-processed assets. * Add support for hot-reloading CSS and pictures that have been re-processed.

---
title: Code
---

PieCrust can be extended with plugins in order to support additional features
such as new [formatters][1], [processors][2], or [template engines][3] (among
other things).

[Creating a plugin][4] is very easy in itself, but requires making a
`setuptools` package in order to be easily shared with other people.


[1]: {{docurl('content/formatters')}}
[2]: {{docurl('asset-pipeline')}}
[3]: {{docurl('content/templating')}}
[4]: {{apiurl('plugins')}}