Cloud Imperium Games announced today that its Star Citizen and Squadron 42 games will use the Amazon Lumberyard game engine. These are two of the most ambitious games being built today, and the switch from other engines is a coup for Amazon.

Previously, Cloud Imperium Games indicated it was using the CryEngine, from Crytek. But Crytek has been having financial troubles, and the Lumberyard engine is a derivative of the CryEngine, as Amazon paid $50 million to license it so that the company could modify and build Lumberyard.

By switching to Lumberyard, Cloud Imperium Games will get the benefits of the new engine, which includes deep integration with Amazon Web Services (AWS) online infrastructure and Twitch livestreaming. And since Star Citizen is an online space simulation game (it’s from Chris Roberts, the driving force behind the original Wing Commander space combat sims), it could benefit from any engine that works well with AWS.

Amazon probably views its game engine as a loss leader. It gives it away for free, but it gains high profile customers for its web services and other businesses.

Cloud Imperium Games said it has raised $139 million in crowdfunding for its space simulation games. Star Citizen was announced in October 2012, but it hasn’t released yet — and no launch date is imminent.

Amazon describes Lumberyard as a free triple-A (industry term for blockbuster), cross-platform 3D game engine that empowers game developers to create the highest-quality experiences, connect their games to the vast compute and storage of the AWS Cloud, and engage fans on Twitch.

“We’ve been working with Amazon for more than a year, as we have been looking for a technology leader to partner with for the long term future of Star Citizen and Squadron 42,” said Roberts, Cloud Imperium Games’ CEO and creative director, in a statement. “Lumberyard provides ground breaking technology features for online games, including deep back-end cloud integration on AWS and its social component with Twitch that enables us to easily and instantly connect to millions of global gamers. Because we share a common technical vision, it has been a very smooth and easy transition to Lumberyard. In fact, we are excited to announce that our upcoming 2.6 Alpha release for Star Citizen is running on Lumberyard and AWS.”

And Amazon is happy to have showcase games on its young game engine.

“Star Citizen and Squadron 42 are incredibly ambitious projects which are only possible with great engine technology paired with the transformative power of the cloud. We love how CIG’s bold vision has already inspired a massive community, and we’re thrilled to see what they create with Lumberyard, AWS, and the Twitch community,” said Dan Winters, head of business development for Amazon Games. “We’re excited that they’ve chosen Lumberyard and AWS to provide the performance and scalability they need to bring their games to a massive audience.”

Added Roberts, “We are delighted to be working with a partner with the strength, vision, and resources of Amazon Web Services. We are looking forward to developing our relationship with AWS and the Lumberyard community in the future.”