Do elaborate more on this pathway? Can this be a proper Dev Env without needing Mac/ Mac OSX on a VM?
You can run Swift on Ubuntu 14.04 and Ubuntu 15.10 (no support for 16.04 as of this writing) Go to
Swift.org and follow the instructions. If you are looking for an IDE, there isn't one, however you can hack one up using Atom as described in
this article. It will allow you to build and run (perhaps distribute to other Linux platforms) Swift applications but that's it. It is not a way for you to submit applications to the App Store, for now it's mostly just a way to sharpen your skills with Swift without a Mac/OS X VM. The latest version available is 2.2.1.
I could elaborate for hours on this but I think you'll find all the information already written in the two links I shared. No sense in making you read it twice.
1) Install Ubuntu 14.04 or Ubuntu 15.10
2) Download Swift from here -
https://swift.org/download/
3) Read up on how to install it for your platform under Getting Started > Installing Swift -
https://swift.org/getting-started/#installing-swift
4) Make a decision, use the REPL that comes with it, or go here and follow the instructions -
https://medium.com/@Aciid/hacking-a...runs-on-linux-and-mac-c7d9520a0fac#.7qzndp63t
5) Learn/Start using Swift.
Swift.org includes some of the basics from the Swift book, or you can browse the Swift 2.2 book at developer.apple.com for more information.
Like I said, you won't be able to build iOS apps, but you will be able to build apps that run on Linux and Mac. You can import Glibc or Darwin depending on where (Linux/Mac respectively) the application will run.