Hello all,

I'm trying to create a package definition, following mainly the manual
pages :
- Packaging Guidelines
<https://www.gnu.org/software/guix/manual/html_node/Packaging-Guidelines.html#Packaging-Guidelines>
- Defining-Packages
<https://www.gnu.org/software/guix/manual/html_node/Defining-Packages.html#Defining-Packages>
- and Debugging-Build-Failures
<https://www.gnu.org/software/guix/manual/html_node/Debugging-Build-Failures.html#Debugging-Build-Failures>

In the attached .scm file, here is what I gathered it might look like as a
first try.
The thing is that I can not debug the build process, even though I use the
--keep-failed option : I'm not getting a temp build directory
(/tmp/guix-build-...) as I expect :
arnaud@brix ~$ guix build -f /home/arnaud/freefilesync.scm --keep-failed
guix build: error: #<unspecified>: not something we can build
arnaud@brix ~$ cd /tmp/
babel-10188XJP/      guix-inst/           mozilla_arnaud0/
emacs-guix-101889w1/ icecat_arnaud/       .overlayfs-workdir/
.esd-1000/           .ICE-unix/           .X11-unix/
arnaud@brix ~$
One thing to add is that the downloaded source file is not tar.gz file
format but zip file, perhaps that's part of the problem ?
This is a GuixSD install with guix pull done yesterday.

Thanks in advance
Arnaud
<https://www.gnu.org/software/guix/manual/html_node/Defining-Packages.html#Defining-Packages>