Electric Runway founder Amanda Cosco takes you inside Silicon Valley to the Poshmark headquarters to meet co-founder Tracy Sun. Poshmark is a leading platform for buying and selling fashion. Poshmark invites you to shop the closets of women across America, and gives you the opportunity to sell items from your closet. While the company may have emerged as a pioneer of recommence —that is, the reselling of used goods online—today, four-and-a-half years later, the company has its sights set on something much bigger.