def paginate_articles
  # Get articles
  articles = items.select { |i| i[:kind] == 'article' }.sort_by { |a| Time.parse(a[:created_at]) }

  # Paginate articles
  article_groups = []
  article_groups << articles.slice!(0..config[:page_size]-1) until articles.empty?

  # Create pagination pages
  article_groups.each_with_index do |articles, i|
    # Create item
    items << Nanoc3::Item.new(
      "<%= render 'pagination_page', :articles_per_item => #{config[:page_size]}, :item_id => #{i} %>",
      { :title => "Blog - Archive (#{i+1})" },
      "/blog/#{i+1}/"
    )
  end
end

before do
  paginate_articles
end