Project Types
Game
This one is obvious, everything exists within a game.
Library
The library project is our equivalent of nuget packages.
You can create a common library of code and publish it as a package. This enables you to re-use the same code over multiple games by adding the package as a reference.
Once you have made your library public you should be aware that if you remove or change the public API of the assembly you risk breaking projects that are referencing it.
In the future we'll be offering tools to help avoid this situation, like letting you reference a specific version of a package, and letting you test your library changes against other packages that are referencing it before publishing
Addon
Addons no longer exist. They will come back eventually, but they're low priority.
Addons allow you to build on top of and modify existing games.
Addons can target a specific game, or work universally across all games. Though not every game will support loading addons.
Tool
https://docs.facepunch.com/s/sbox-dev/doc/editor-project-LuRHQgnNjC
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Rust
Steamworks
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