The Core Animation-based UI framework used in Twitter for Mac.

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One recent town-square meeting, in fact, was devoted to the aesthetic virtues of the Golden Gate Bridge. “We’re the only payments company in the world that’s concerned with design,” the Prada-clad Dorsey begins. He shows a dramatic photo of the bridge taken from atop one of its towers. “This is what I want to build. This is classy. This is inspiring. This is limitless. Every single aspect of this is gorgeous. . . . So your homework this weekend is to cross this bridge, think about that, and also think about how we take those lessons into doing what we do, which is carry every single transaction in the world.”
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"Sure, I'm serious. What possible reason could a person have for saying something amusing that's not true? There's no "Fiction" on the web."

The super-light online chat app that uses Twitter for authentication. Invite people via DM.