Code 1

Can you crack this code? It's deligthfully simple once you understand it, yet may be dreadfully difficult to solve.

The image is small, I know; to be clear, the whole thing is one continuous line, starting from the left and zigzagging around. The nodes may or may not matter.

If you want a hint, transpose each of the following letters to the letter before it (and each number to the number before it):

Uijol cbtf-9.

Have fun!