Format dates and sort archive posts descending by date

src/pages/archive.js

@@ -11,10 +11,13 @@ export default function Archive({ data }) {
 	});
 
 	const yearGroupsHtml = yearGroups.map(yg => {
+		yg.edges.sort(function(a,b) {
+			return new Date(b.node.frontmatter.date) - new Date(a.node.frontmatter.date);
+		});
 		const postListItems = yg.edges.map(({node}) => {
 			return (
 				<li>
-					<a href={node.fields.slug}>{node.frontmatter.date} - {node.frontmatter.title}</a>
+					<a href={node.fields.slug}>{node.frontmatter.shortDate} - {node.frontmatter.title}</a>
 				</li>
 			);
 		});
@@ -48,7 +51,8 @@ export const query = graphql`
 					}
 					frontmatter {
 						title
-						date(formatString: "MMM Do")
+						date
+						shortDate: date(formatString: "MM/DD")
 					}
 				}
 			}