The game is nice, it needs to be expanded a bit, perhaps by adding boosts after each wave. At the beginning it's too slow since there are too many waves with a single enemy, but later it becomes very fun when more enemies start appearing together and each enemy has a different level of resistance and speed. But I didn't really understand if I had to defend the turret or the street that was behind the turret. It takes a little background. Overall it's a lot of fun but could be improved.
P.S. I love the music you used, it takes me back to the games I played as a child ^^