You can buy the standalone version of DayZ on Steam right now.

Developer Bohemia Interactive released DayZ on Steam’s Early Access portal today. This is a heavily upgraded version of the DayZ mod that originally added zombies and other survival elements to Arma II. The studio built this version to work independently of its military shooter.

DayZ is in alpha, and Bohemia Interactive is selling it for $30.

“DayZ Early Access is your chance to experience DayZ as it evolves throughout its development process,” reads a post Bohemia Interactive’s Steam page. “Be aware that our Early Access offer is a representation of our core pillars, and the framework we have created around them. It is a work in progress and therefore contains a variety of bugs. We strongly advise you not to buy and play the game at this stage unless you clearly understand what Early Access means and are interested in participating in the ongoing development cycle.”

Early Access is a separate channel for games on Steam that are not yet finished. People can purchase access to the titles and play along as studios continue improving them with updates. As developers make improvements, they typically raise the price of their games as they hit beta and the final release, but Early Access players get those updates at no additional charge.

In DayZ, gamers inhabit a server with other live players and computer-controlled zombies. Players must collect gear, weapons, and food to survive in the harsh open-world game. The mod quickly racked up more than a million players, and its developer, Dean Hall, moved on to develop the standalone version with Bohemia Interactive.