Add the middleman-blog-authors gem to you Gemfile.
gem "middleman-blog-authors"
Activate this extension in your config.rb file
activate :authors
In your blog posts, add authors to the metadata:
---
title: Building Middleman Extensions
date: 2013-07-17
authors: Darby Frey
---
Create a template for the author page. If this is not your default template, put it in source/layouts:
source/layouts/author.html.haml
---
title: #{author.name}
pageable: true
per_page: 10
---
<h1><%= author.name %></h1>
<ul>
<% page_articles.each do |article| %>
<li><%= link_to article.title, article %></li>
<% end %>
</ul>