This is not anything new, but the instructions are a bit buried so I'm hoping that this write-up saves the next person the "duckduckgo-ing" and comment-reading I had to do.

First, what are we talking about. By Series, I'm talking about the badge that appears at the top of certain posts. For example, take a series of Book Notes by @danlebero the top of each post is decorated with links to the other posts in the series:

If you want to create a series, you can do so using the "Rich" editor as shown here:

A short guide on how to “make” the series widget on DEV

Dzhavat Ushev ・ Sep 27 '19 ・ 2 min read

#meta

Unfortunately, once you set the series value via the rich-editor, it won't switch back to the Markdown editor even if you revert your settings. I quite prefer the writing & thinking in markup so this was quite a deal-breaker for me.

After hunting around the comments, I found the answer in the last place I'd look: The User Manual, in the Front Matter section. Here's what the meta-data for this post looks like:

--------
title: Create a "Series" from Markdown Editor
published: true
description: You ever wondered how people are creating a series of posts here on dev.to? Wonder no more
tags: howto, tutorial, guide
series: "Publishing on Dev.to"
--------

Basically, you just set the series key in the header and the new post gets added to the series.

Thank you for reading, let me know if this works for you and give it a ❤️ if it saved you some time so it's easier for others to find it. 🙏