Eye tracking is starting to be used for evaluation and interaction in virtual environments. Especially digital games can benefit from an integrated approach, using eye tracking technology for analysis and interaction. One benefit is faster development of gaze interaction games, which can be automatically evaluated in iterative development cycles. For this purpose, we present a framework of programming libraries that enables rapid game development and gameplay analysis within an experimental research environment. The framework presented here is extensible for different kinds of logging (e.g., psychophysiological and in-game behavioral data) and facilitates studies using eye-tracking technology in digital entertainment environments. An experimental study using gaze-only interaction in a digital game is presented and highlights the framework's capacity to create games and evaluate novel entertainment interfaces. © 2010 International Federation for Information Processing.