Guillermo:

>  *
>
>     The |wall|(1) program is available in Void's 'standard'
>     executables directories.
>
> Because that's what nosh's build system and executables are going to 
> expect, as far as I know.
>
For the sake of other readers: note that it is not the build system that 
employs the |wall| program.  (That would be bizarre.)  It is the 
|shutdown| program, at runtime, as described in its manual.  This is not 
a requirement specific to the nosh toolset's |shutdown| program. The old 
|shutdown| program in FreeBSD and OpenBSD has the same requirement, for 
example, as did the |shutdown| program in 386BSD.  Using the |wall| 
program to do its job rather than duplicating (a fork of) its code into 
|shutdown| (which the van Smoorenburg 
<https://sources.debian.org/src/sysvinit/2.88dsf-59.10/src/dowall.c/>, 
upstart 
<https://bazaar.launchpad.net/%7Eupstart-devel/upstart/trunk/view/head:/util/shutdown.c#L672>, 
and systemd 
<https://github.com/systemd/systemd/blob/b0450864f1723ad12176d7956377d89ff4a84d8c/src/shared/utmp-wtmp.c#L361> 
|shutdown| programs all have) has a long history in the Unix world.