Hello—

To synchronise file with a server I don't operate, I would like to use
unison@2.48.15 on my Guix System, preferably the GUI*.  The last e-mail
I could find about this on the mailinglists looks relevant.

Je 2 apr 2018 16:16 skribis Leo:
> On Mon, Apr 02, 2018 at 02:10:22PM +0200, Arnaud B wrote:
> > I looked at the ocaml.scm file where the unison package is defined,
> > together with ocaml, lablgtk and a number of other related tools. It uses
> > the gtk module (gnu packages gtk), in which there is pango as well.  
> 
> > So it seems everything is in place to build unison and at the same time its
> > graphical version, according to the build instructions
> > <https://webdav.seas.upenn.edu/svn/unison/branches/2.48/src/INSTALL.gtk2>
> > given for that.
> > But in the end in my GuixSD as the user having done the installation, I
> > just end up with the CLI unison and not unison-gtk2 as expected.
> > I tried explicitly installing various packages such as gtk+, lablgtk, and
> > then rebuilding the unison package, to no avail.  
> 
> Basically, the packages that are required to build the Unison GUI, such
> as lablgtk, GTK+ itself, etc, are not present in the environment where
> Unison is built by Guix. They may be defined in the same source file as
> the Unison package, or they may be imported by that file, but this does
> not mean they are present in the Unison build environment. Additionally,
> installing a package with `guix package --install` has no effect on how
> packages are built.
> 
> Each time Guix builds a package, it uses an isolated environment that
> only includes the software specified in the package definition of the
> package being built, as well as "implicit" dependencies that come with
> the specified build system.
> 
> To make progress on building the Unison GUI, I recommend adding the
> required packages to a new inputs field in the Unison package
> definition. You can copy the structure of the native-inputs field for
> this.
> 
> I recommend reading the Introduction of the Guix manual [0], and
> continuing to other sections as your interest allows. You will also find
> some useful info in Package Reference [1].
> 
> Please don't hesitate to ask more questions here or on the Guix IRC
> channel, #guix on Freenode.
> 
> [0]
> https://www.gnu.org/software/guix/manual/html_node/Introduction.html
> 
> [1]
> https://www.gnu.org/software/guix/manual/html_node/package-Reference.html

Arnaud, did you ever look into this again?  Did you find a solution for
synchronising between Guix and the other system?

I vaguely remember that at some time there were several Unison versions
available on Guix.

Of course, I might try to build Unison 2.51.2 on the non-Guix system.

—Marco

* Works nice to put unison-gtk in .xinitrc, before and after running
  your window manager.