Currently, rpkg builds packets by tar'ring and gzip'ping the source
directories through GNU tar.

However it aims to be entirely Ruby-based or at least platform
independent out of the box.  If you have any though or warning on the
following subjects, I'd like to hear them:

- is GNU tar a reasonable external requirement for this, i.e. is it
easily available on every platform that Ruby runs on or even

- do backquotes for calling external commands work reliably and
uniformly across supported platforms?  In other words, will writing
tar xcf #{pkgdir} always do the trick or will it need tweakings
depending on the platform?  I'm thinking in the direction of
C:\full\path\to\tar zcf #{pkgdir} on Windows, which I don't know if
can be avoided (how do you Windows folks usually do?).

- alternatively, is there any reasonable pure Ruby solution?  I have
seen CompressionR, Rubyzip, and Ruby/zlib in the RAA.  Could someone
who has used them a bit if not extensively suggest whether the answer
is among them?

Massimiliano