The team behind the long-in-development Black Mesa, a "re-envisioning" of Valve's original Half-Life, will bring its game to Steam as a commercial product, the developer announced today. And they'll be doing so using a newer version of Valve's Source engine.

"We never developed Black Mesa with money in mind," the team wrote in an update. "Our team is made up of average, hardworking people, and no one joined the team to make money. For us, Black Mesa is purely a labor of love. We believe this philosophy has significantly contributed to the overall quality and feel of the game."

The team says it plans to sell Black Mesa in an effort to "make the game even better by having full access to the Source engine" and for financial reasons. "Frankly, our team could really use the financial help," the post reads.

In addition to the retail version that will launch "soon" for a "relatively low price," the Black Mesa developers say they'll release a completely new free version of the game and plans to open source maps and certain assets to the modding community.

"Purchasing the Steam version of Black Mesa is more about supporting the team and our efforts than anything else," the team says. "However, the Steam version will include features that the free version simply can not have. We will be paying careful attention to feedback, and you'll have a very real say in how the final game turns out."

Black Mesa's developer says it continues to work on the Xen portion of the game and that the past year has been spent bringing the title to a newer version of the Source engine. "The work to port to the new engine was not because of the decision to go retail, this was work that had to be done to get Black Mesa onto Steam and support our future plans," the team says.

In development in various forms since 2004, Black Mesa was one of the first titles to pass the Steam Greenlight process last year. For more on the development of the game, read our interview with Black Mesa's project leader.