diff --git a/packages/gatsby-plugin-feed/README.md b/packages/gatsby-plugin-feed/README.md
index 6be37298cfe10..5bb352528d187 100644
--- a/packages/gatsby-plugin-feed/README.md
+++ b/packages/gatsby-plugin-feed/README.md
@@ -45,15 +45,15 @@ plugins: [
       feeds: [
         {
           serialize: ({ query: { site, allMarkdownRemark } }) => {
-		    return allMarkdownRemark.edges.map(edge => {
-		      return Object.assign({}, edge.node.frontmatter, {
-		        description: edge.node.excerpt,
-		        url: site.siteMetadata.siteUrl + edge.node.fields.slug,
-		        guid: site.siteMetadata.siteUrl + edge.node.fields.slug,
-		        custom_elements: [{ 'content:encoded': edge.node.html }],
-		      });
-		    });
-		  },
+            return allMarkdownRemark.edges.map(edge => {
+              return Object.assign({}, edge.node.frontmatter, {
+                description: edge.node.excerpt,
+                url: site.siteMetadata.siteUrl + edge.node.fields.slug,
+                guid: site.siteMetadata.siteUrl + edge.node.fields.slug,
+                custom_elements: [{ 'content:encoded': edge.node.html }],
+              });
+            });
+          },
           query: `
             {
               allMarkdownRemark(