}
            # Hack to handle timeouts, which Nix doesn't report
            # properly when they occur remotely.  If we get a "hook
            # failed" error and $maxsilent seconds have passed since
            # the start of the build step, then assume that a timeout
            # occured.
            if (/^@\s+hook-failed\s+(\S+)\s+(\S+)\s+(\S+)\s+(.*)$/ && $3 eq "256") {
                my $drvPathStep = $1;
                if ($buildSteps{$drvPathStep}) {
                    my $step = $build->buildsteps->find({stepnr => $buildSteps{$drvPathStep}}) or die;
                    print STDERR $step->starttime, " ", time(), "\n";
                    if ($step->starttime + $maxsilent <= time) {
                        $_ = "@ build-failed $1 $2 timeout $4";
                    }
                }