An intern at Facebook has landed a dream job at the social networking site after building the company's new mobile advertising tool.
Peter Cottle, who is studying mechanical engineering at the University of California, Berkeley, took on the ambitious project within a week of starting his placement.
His idea, which uses an interface designed by another intern, Leo Mancini, lets the owners of Facebook pages buy mobile advertising using a mobile device.
It combines two mechanisms already created by Facebook which allowed businesses to promote a post to their fans and to update their pages and interact with clients via the iOS device.
The advertising tool has now been rolled out as part of the Facebook Pages Manager app, which is available from the App Store.
Mr Cottle, 23, said: "It felt great to put so much effort into a historic interface and see our work make the ship deadline.
"I'm really proud of the feature, thankful for the opportunity and excited to demonstrate Facebook's dedication towards mobile."
Launched in 2004, Facebook now has more than one billion active users - 600 million of them on mobile devices.
The technology giant, which is based in Menlo Park, California, employs nearly 4,000 people.
In a post he wrote for the Facebook Engineering blog, Mr Cottle said a typical day at the company involves "downing juicy ribs from our BBQ shack, winning some bragging rights at the foosball table, and then hacking away into the night at an intern hackathon."