eval {
  TX:
    {
        # step 1: database
        $dbh->do("CREATE DATABASE foo");
        push @undo, sub {
            $dbh->do("DROP DATABASE foo");
        };

        # step 2a: filesystem
        mkdir "/path/foo" or last TX;
        push @undo, sub { rmdir "/path/foo" };

        # step 2b
        push @undo, sub { remove_tree "/path/foo" };
        create_a_bunch_of_files_in("/path/foo") or last TX;

        # step 3: logger (usually also on filesystem)
        write_log("Database and files setup") or last TX;

        # step 4: email (it's okay to fail this step)
        send_email('foo@bar.com');

        # mark success
        @undo = ();
    }

    # rollback, we force each step even though it dies
    for (reverse @undo) {
        eval { $_->() };
    }
};