Filter posts out of RSS feed based on tag?

I do this on my RSS feed, it works the same way in any other template.

I wrap the portion in the feed with the excluded tag, i.e. apples:

{{^tagged.apples}}
  <item> 
    <title><![CDATA[ {{{title}}} ]]></title>
    <link>{{{absoluteURL}}}</link>
    <guid>{{{absoluteURL}}}</guid>
    {{! RSS feeds need a RFC 822 date}}
    <pubDate>{{#formatDate}}ddd, DD MMM YYYY HH:mm:ss ZZ{{/formatDate}}</pubDate>
    <description><![CDATA[ {{#absoluteURLs}} {{{body}}} {{/absoluteURLs}} ]]></description>
  </item>
{{/tagged.apples}}

-Ray

Would it be possible to use a version of this technique to output a feed for just one tag?

Yes! To convert a feed which ignores posts tagged apples, to a feed which only shows posts tagged apples, use the example above but replace this:

{{^tagged.apples}}

With this:

{{#tagged.apples}}

There's more about sections and inverted sections in the docs.

Thanks – much appreciated. Let the tinkering commence.

I'm using the above method to limit posts tagged with 'linkpost' in my RSS feed. I'd also like to limit posts tagged with 'meta', since those are internal site mechanics posts that I think aren't for broad consumption.

What's the proper syntax to have multiple tags in the. exclusion criteria vs. just the one?

I found the nested tag syntax in an answer to another post question.