Use Layout to build a main/sidebar layout.
<%= render(Primer::LayoutComponent.new) do |component| %>
<% component.with(:sidebar) { "Sidebar" } %>
<% component.with(:main) { "Main" } %>
<% end %>
<%= render(Primer::LayoutComponent.new(side: :left)) do |component| %>
<% component.with(:sidebar) { "Sidebar" } %>
<% component.with(:main) { "Main" } %>
<% end %>