That's a deflection and avoiding an answer. You say that you do not know what is happening under the hood. There's a published archive of program source code

That's a deflection and avoiding an answer. You say that you do not know what is happening under the hood. There's a published archive of program source code to read. So what is stopping you from reading it and finding out what the program does under the hood? Difficulty with tar? Or with xz?