On February 5, 2002, Sunspire Studios released in retail a closed-source and commercial expansion of the game titled Tux Racer, with each CD designed to support both Linux and Windows operating systems.[12][13] Improvements from the open-source version include a vastly enhanced engine and graphics, the ability to perform tricks, character selection, and competitive multiplayer.[14] The open-source version of Tux Racer, however, remained available to download on SourceForge.[4]: 191 Sunspire Studios ceased business in the early- to mid-2000s.[12]