gistfile1.txt

        $!promise = start {
            my $p = run(
                $*EXECUTABLE,
                @!includes.map({ qqw/-I$_/ }),
                $!file,
                :out, :err, :cwd($!path)
            );
            repeat until $p.out.eof {
                $!stdout.emit($p.out.getc);

                if $p.?err && !$p.err.eof {
                    if (my $v = $p.err.getc).defined {
                        $!stderr.emit($p.err.getc);
                    }
                }
            }
            $!stdout.done;
            $!stderr.done;
            $!merge.close;
        }