shprung

<p>Less than 40 lines of php code so it will not slow your site and if all you<br />
need is to add an rss feed, give it a try.</p>
<p><em>You can even setup the output template – something many other plugin don’t<br />
offer</em>.</p>
<h3>A brief Markdown Example</h3>
<pre><code>short code examples:

[rss url="http://www.usacycling.org/rss/headlines.rss"]


[rss url="http://www.usacycling.org/rss/headlines.rss" no="20" target="_self"]

You can change the template used via wp-admin/options.php , look for
'rss_shortcode_template'
Template fields documentation:
    _TITLE_  : the rss feed title line
    _LINK_   : the link to the complete store, aka permalink
    _MSG_    : the short message/description; the first few 
               lines of the post/story
    _DATE_   : post date & time
    _TARGET_ : the link target
</code></pre>


RSS shortcode w/template

lets you embed rss feed in any WordPress content (e.g., pages, posts, custom post types) using Shortcode.

Matthias Pfefferle

IndieWeb

joshfraz

<p>This plugin implements the <a href="https://www.w3.org/TR/websub/" rel="nofollow ugc">WebSub</a> protocol (formerly known as PubSubHubbub) for WordPress. It enables real-time notifications when your blog is updated and provides a subscriber API for other plugins to consume WebSub-enabled feeds.</p>
<h3>Publisher Features</h3>
<p>When you publish or update a post, this plugin automatically notifies WebSub hubs, which then distribute the update to all subscribers in real-time.</p>
<ul>
<li>Sends realtime notifications when you update your blog</li>
<li>Supports multi-user installations (WordPress MU)</li>
<li>Supports multiple hubs</li>
<li>Supports all feed formats used by WordPress (Atom, RSS2, RDF)</li>
<li>Adds <code><link rel="hub"></code> and <code><link rel="self"></code> declarations to feeds and HTML</li>
</ul>
<h3>Subscriber Features</h3>
<p>The plugin provides a subscriber API that allows other plugins (like feed readers) to subscribe to WebSub-enabled feeds using WordPress hooks.</p>
<ul>
<li>REST API callback endpoint for subscription verification and content delivery</li>
<li>Hub discovery from topic URLs (HTTP Link headers and feed content)</li>
<li>HMAC signature verification (SHA1, SHA256, SHA384, SHA512)</li>
<li>Full lifecycle hooks for integration with other plugins</li>
</ul>
<h3>Supported Specifications</h3>
<ul>
<li><a href="https://www.w3.org/TR/websub/" rel="nofollow ugc">WebSub W3C Recommendation</a></li>
<li><a href="https://pubsubhubbub.github.io/PubSubHubbub/pubsubhubbub-core-0.4.html" rel="nofollow ugc">PubSubHubbub 0.4</a></li>
</ul>
<h3>Default Hubs</h3>
<p>By default this plugin will ping the following hubs:</p>
<ul>
<li><a href="https://pubsubhubbub.appspot.com" rel="nofollow ugc">Demo hub on Google App Engine</a></li>
<li><a href="https://pubsubhubbub.superfeedr.com" rel="nofollow ugc">SuperFeedr</a></li>
<li><a href="https://websubhub.com" rel="nofollow ugc">WebSubHub</a></li>
</ul>
<p>Please contact us if you operate a hub that you would like to be included as a default option.</p>


WebSub (FKA. PubSubHubbub)

Best Update Plugin

A WebSub plugin for WordPress that enables real-time publishing and subscription capabilities.

RSS shortcode w/template vs WebSub (FKA. PubSubHubbub)