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Valve hands the Team Fortress 2 source code to modders
Team Fortress 2 modders can now do just about whatever they want with the game — as long as they don't try to make money from creations based on the source code.
The main catch is that Valve is offering the TF2 source code on a non-commercial basis, so any mods or content therein that are based on the SDK have to be available for free. The company also notes that much of the content that's in players' inventories — most of the in-game items, in fact — were created by the Steam Workshop community. Giving fans the client and server code could be a sign that Valve is ready to wind down official support for the game.
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