The basis of GoldSrc is the engine used in the video game Quake, albeit with heavy modification by Valve.

[2] In 1997, Valve hired Ben Morris and acquired Worldcraft, a tool for creating custom Quake maps.

[17] Counter-Strike and Day of Defeat were also originally Half-Life modifications that Valve purchased the rights to and re-released as standalone titles.

Notable games include Natural Selection, Cry of Fear and Sven Co-op, with Valve's Team Fortress Classic, Counter-Strike, and Day of Defeat all being based on GoldSrc mods of the same names.

Sven Co-op have since been released for free as a standalone game on Steam, which use a licensed derivative of the engine with their own customizations.

The Xash3D project and forks use Quake engine source code in part, as well as the Half-Life SDK, to recreate GoldSrc and run its various mods on different platforms.