Adding Swift 3 packages to Xcode 8 using the Swift package manager
Xcode and the SPM can work together, but as far as I can tell you do need to take one step on the command line.
Put your package manifest file into the same directory as the Xcode project, and then invoke swift package generate-xcodeproj
The package manager will pull down your dependencies and rewrite the .xcodeproj file to refer to them.
It will preserve any existing source, but the directory structure will be reconfigured to SPM's preferred arrangement:
PROJECT_DIR├── Sources│ └── ProjectName│ ├── YourCode.swift│ └── YourOtherCode.swift├── Dependencies│ └── SomeDependency│ ├── DependencyCode.swift│ └── OtherDependencyCode.swift└── Package.swiftN.B., I haven't tested this extensively on a live project; given the fact that SPM docs still say WIP, please make sure you've made a recent commit.
In addition to running swift package generate-xcodeproj, I had to build my project in Xcode before I could use the installed packages.