{ stdenv, writeScriptBin, runtimeShell }:
let fake = name: stdenv.lib.overrideDerivation (writeScriptBin name ''
#!${runtimeShell}
echo >&2 "Faking call to ${name} with arguments:"
echo >&2 "$@"
'') (drv: {
name = "${name}-stub";
}); in
{
setfile = fake "SetFile";
rez = fake "Rez";
derez = fake "DeRez";
}