List of commercial video games with later released source code

The source code of these commercially developed and distributed video games is available to the public or the games' communities.

Commercial video games are typically developed as proprietary closed source software products, with the source code treated as a trade secret (unlike open-source video games). When there is no more expected revenue, these games enter the end-of-life as a product with no support or availability for the game's users and community, becoming abandonware.

In several of the cases listed here, the game's developers released the source code expressly to prevent their work from becoming abandonware. Such source code is often released under varying (free and non-free, commercial and non-commercial) software licenses to the games' communities or the public; artwork and data are often released under a different license than the source code, as the copyright situation is different or more complicated. The source code may be pushed by the developers to public repositories (e.g. Sourceforge or GitHub), or given to selected game community members, or sold with the game, or become available by other means. The game may be written in an interpreted language such as BASIC or Python, and distributed as raw source code without being compiled; early software was often distributed in text form, as in the book BASIC Computer Games. In some cases when a game's source code is not available by other means, the game's community "reconstructs" source code from compiled binary files through time-demanding reverse engineering techniques. Source code availability in whatever form allows the games' communities to study how the game works, make modifications, and provide technical support themselves when the official support has ended, e.g. with unofficial patches to fix bugs or source ports to make the game compatible with new platforms.

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