"We didn't actually get that much better projects than we do [now]," Atlassian's Ryall says.
"We found with the longer ShipIt that it didn't actually have that much impact on what people could achieve. And people just aimed for much larger project and got less [of the way] through a bigger project than they would have with a smaller one, so we scaled it back to the two-day format again."
Although the aim is to encourage creativity, Yahoo!7's Penfold says that it helps to add at least some structure and direction. "The way we do that is we hack around categories, so for example the best app or the best hack that's externally facing that matches our strategy on our key properties," he says.
"We allow as much flexibility as we need, but also try to target and focus it a bit to really help guide people in what they do and being fairly fixed on the time [period for the hack day]."
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