You can execute the process under sandbox-exec to take advantage of OS X kernel-level sandboxing. You'll need to write your own profile file that allows/denys what you want. There are plenty of examples of these .sb profile files under /System/Library. More: https://developer.apple.com/library/mac/documentation/Darwin...
It's possible that by the end of this week, maybe next, it will be very easy indeed to compile and/or run Swift on Linux from Linux, at which point you could try LXC or a million other ways to virtualize.
This mechanism has been deprecated by Apple. In the header file they point out that one should use the OS X sandboxing instead which works with plists instead and can be controlled with less flexibility.
Calling sandbox_init from inside your app has been deprecated in favor of the App Sandbox mechanism, but I don't see any indication that sandbox-exec is deprecated.
