Designer, developer, and advisor. Building Pierre. Advising with growing teams at Studio MDO. Creator of Bootstrap. Previously at GitHub and Twitter. Huge nerd.

Mark Otto is a designer, developer, and advisor in the San Francisco Bay Area. In 2007, he dropped out of college and moved to California to work at a design agency where he designed and developed dozens of projects for clients like Photobucket, Facebook, and his personal favorite, Britney Spears.

In 2008, he became a Product and Platform Designer at Twitter working on Promoted Tweets, Twitter.com during #NewNewTwitter, the Twitter Help Center, and several internal tools.

While at Twitter, he also created the popular open source front-end toolkit Bootstrap with @fat. In late 2012, he left to join GitHub as a Product Designer.

At GitHub, he worked on GitHub Enterprise, redesigned Issues, redesigned conversations, designed split diffs, shipped mobile web notifications, and iterated on GitHub.com’s overall aesthetic with ships like redesigned repositories, system fonts, dark header, and more.

From 2015 to 2017, he served as Director of Design, growing and managing a team of 30 designers, artists, and writers across Product and Marketing.

In 2017, the GitHub Product and Marketing Design teams split and he took over the Marketing half as Senior Director of Design. For over two years, he managed an extremely talented team of web designers, engineers, videographers, and artists that maintained GitHub’s brand, marketing sites, and creative campaigns.

In July 2019, he left management to become GitHub’s first Principal Designer, focusing on designing, building, and shipping various brand projects, marketing sites, and other special projects. Some highlights include The GitHub Shop, special projects like GitHub’s intranet (aka The Hub), and keynotes for GitHub Universe and GitHub Satellite.

Since late 2021, he’s been working with growing companies as an advisor and contractor on product design, marketing, narrative and storytelling, web design, and brand design under the moniker Studio MDO. Clients have included Vercel, Zed, Dragonfly, and more.

In March 2023, after spending more than 10 years there, he left GitHub to work on something different at Pierre.


  • Chief Product Officer · Pierre
  • Founder & Designer · Studio MDO
  • Principal Designer · GitHub
  • Senior Director of Design · GitHub
  • Director of Design · GitHub
  • Senior Product Designer · GitHub
  • Product Designer · Twitter
  • Designer · ZURB

About the site

This URL has been my online home for many years, manifesting at times as a blog or a portfolio until landing on this current single-column blog. In case you were wondering, this site is:

You can find more about my macOS development setup in my config repo on GitHub. The design and code powering this site, however, is not available for re-use or purchase.

For comments or questions, send me an email at markdotto at gmail dot com.