The folks at Chucklefish Games announced today that less than a year after its 1.0 debut, their procedurally-generated 2D game Starbound has sold over two and a half million copies.
It's a significant sales milestone for the project, which was publicly announced in 2012 and put up for pre-order in 2013 -- at which point it generated $1 million in sales in under three weeks.
The game was put up on Steam's Early Access service at the end of 2013, and presumably this latest sales figure encompasses all units sold over the past 4+ years.
According to Chucklefish's blog, development on the game is expected to continue for the foreseeable future.