Pages of content in Nesta CMS can be embellished with metadata, written in a simple key/value pair syntax. If you'd like extra flexibility in your metadata, you can use this plugin to replace Nesta's built-in metadata parser with Ruby's Yaml parser.
You still need to make sure that all the metadata is at the top of the page; the first blank line signifies the start of the page content.
To use the plugin just add it to your project's Gemfile and rebuild
your bundle:
$ echo 'gem "nesta-plugin-yaml-metadata"' >> Gemfile
$ bundle
It requires Nesta 0.9.12 or later.