I'm not sure if this is an idiosyncracy with my setup or not, but I had to build skalibs with --with-default-path=/command:/usr/bin:/bin even with --enable-slashpackage set. Without that, execlineb was unable to find any of the execline helper programs.
My confusion was two-fold. First, I'd have expected --enable-slashpackage to jam /command into the built-in path. Secondly, I thought it odd that you set the default path in the backing library and not the interface programs. If it helps, I run s6 in daemontools mode (as opposed to as an init replacement) and the script that starts s6 from my inittab flushes s6's environment so I'm guaranteed to end up with the compiled-in path. Like I said, nothing that couldn't be worked around but there's a good chance that it'll surprise someone else running s6 on Debian. Cheers!
