API 1.1.0 shipped with 0.1.37 and wit/ matched the released snapshot, so additions start with a bump: the package in wit/ and the SDK's copy, ENGINE_VERSION and both API_VERSION constants move to 1.2, and the official plugins and fixtures are rebuilt against it. No interface changes; 1.0 and 1.1 components keep linking. The release that ships 1.2 copies wit/ over the released snapshot.