After building neighborhood social networks in more than 3,000 communities across the U.S., Nirav Tolia has learned just how many different things neighbors can accomplish. Using Nextdoor, the site built by Tolia and his team, neighbors get burglars arrested, investigate possible water poisoning, and stop the installation of parking meters. They lend one another ladders and grills, recommend babysitters, and upload videos of locals.

But the one thing they’re not looking to do is make friends.

“You’re not friends with your neighbors,” Tolia says. “You don’t want to be friends with your neighbors… The communication is a lot more high fidelity if the context is clean.