David Heinemeier Hansson (dhh) extracted Ruby on Rails from his work on Basecamp. He released the framework as open source in July of 2004, but didn't share the commit rights until February of 2005. Among the core team, he's infamous for his ruthless delegation, which is often executed as a request to "Please Do Investigate". He's a partner at 37signals and his personal page is loudthinking.com.

Jeremy Kemper (bitsweat) is a programmer at 37signals hailing from Pasadena, California. Hot on the heels of DHH, he has been the most active contributor to Rails. He's knee deep in pretty much all aspects of the framework and one of the top batters against new, incoming tickets.

Michael Koziarski (nzkoz) is a software consultant based in Wellington, New Zealand. After a successful stint as an enterprise Java developer, he switched to rails shortly after the first public release. He’s a contributor to The Rails Way and maintains a personal blog.

Pratik Naik (lifo) stumbled upon Rails back in 2006 while in search for a better web framework after 2 painful years with perl/mod_perl. He hasn't looked back since then. Currently located in London, he is an employee of 37signals and maintains a personal blog at http://m.onkey.org.

Josh Peek (joshp) has been working with almost all parts of Rails. A lot of work spent on performance and thread safety for Action Pack. He's the latest addition to the team. Josh is an employee of 37signals.

Yehuda Katz is a member of the SproutCore, Ruby on Rails and jQuery Core Teams; during the daytime, he works as Chief Technologist at Strobe. Yehuda is the co-author of the best-selling jQuery in Action, the upcoming Rails 3 in Action, and is a contributor to Ruby in Practice. He spends most of his time hacking on open source -- his main projects, along with others, like Thor, Handlebars and Janus—or traveling the world doing evangelism work. He blogs at http://yehudakatz.com and can be found on Twitter as @wycats.

José Valim (josevalim) is the lead-developer and co-founder of Plataforma Tec. He started working with Rails in late 2006 and began contributing actively after his Google Summer of Code project in 2009. After his Machine Learning master's degree in Italy, he's been flying constantly between Brazil and Poland. Some say that it is his "eureka" time to code and bring new open-source projects to life. Check for yourself what he's up to on his company's blog.

Carl Lerche is a Platform Architect at Strobe, where he runs a top-notch product engineering team and hacks on Strobe Platform. He's been programming for as long as he can remember, and focused on Ruby development since 2005. He is a member of the Ruby on Rails Core Team and speaker at numerous industry conferences and events. He lives in downtown San Francisco and has a fondness for quality Belgian Beers... and pie. Follow him on Twitter at @carllerche.

Santiago Pastorino (spastorino) is one of the lead developers and co-founder of WyeWorks from Montevideo, Uruguay. He started working full-time with Ruby and Rails in the middle of 2008 after years of Java development. Since early 2010 he is trying to work as much as he can on OSS and sporadically writes on his company's blog. Follow him on Twitter at @spastorino.

By day, Aaron Patterson (tenderlove) is a mild mannered programmer for AT&T Interactive whose Ruby code is almost as good looking as him. By night, he dons his Pink Warrior suit which gives him the power to contribute to many Open Source projects such as nokogiri, Ruby, and Rails. If you have seen someone kissing Matz or DHH at a conference, it was probably him. You can find him on twitter, or read his blog.

Xavier Noria (fxn) is an everlasting student and father of the most wonderful girl, as the picture to the left clearly demonstrates QED. An independent Ruby on Rails consultant from Barcelona, Xavier has worked with Rails since 2005. He wrote Rails Contributors and has been a regular contributor for years. Honored to have been presented a Ruby Hero Award, and to be the president of SRUG. Xavier is @fxn on Twitter.

Jon Leighton is a freelance Ruby consultant from Oxford, UK and (probably) the only core member who defiantly refuses to use a Mac! When he occasionally goes AFK, Jon enjoys dangling from small bits of rock on the sides of cliffs and mountains. You can follow @jonleighton, or read his blog.

Rails core members who are no longer active in the day-to-day stuff have been immortalized as core alumni.