This month marks the 20th anniversary of the effort that became the Atom feed format . It all began on June 16, 2003, with a blog post from Apache Software Foundation contributor Sam Ruby asking for feedback about what constitutes a well-formed blog entry. The development of RSS 2.0 had been an unplanned hopscotch from a small group at Netscape to a smaller one at UserLand Software, but Atom was a barn raising.