See Introduction to the buildsystem in the documentation for an overview of the build system. Godot's architecture is very modular and, in fact, the editor is just a part of it you can disable (option tools=no). There are several subsystems: libscene for the scene folder, libplatform for the platform folder, and so on, and they're all compiled statically. Here's a complete list of the options available (you can see them with scons platform=<platform name> --help). I recommend you also look at scons' documentation and Godot's build files (SConstruct) for more knowledge about how to integrate Godot in your own workflow.
But I'm not quite sure what you mean by "Unity-esque workflow": you're talking about the scene system? Or they way it is dealt with in the editor? Because if it's the system itself, that's a core characteristic of Godot you'll to have use even when working only with code.
