Blecharczyk began his career as an Engineer at OPNET Technologies in 2005. He served as a lead developer at Batiq in 2007. In 2008, Blecharczyk partnered with Brian Chesky and Joe Gebbia to found Airbnb, he served as the company's first chief Technology officer and coded the company's original website using Ruby on Rails. Later that year, after failing to raise funding, the founders bought mass quantities of cereal, designed packaging branded as '"Obama O's" and "Cap'n McCain's" cereal to sell at the Democratic National Convention in Denver, Colorado. Originally intended as a marketing ploy, the company sold enough cereal to raise $30,000, and eventually attracted the attention of Y combinator co-founder Paul Graham who gave them $20,000 in early 2009 and accepted the company into the Y Combinator's seed funding program.