Fun defence game! I liked how the game loop felt a little different than most. It was more about rate of replacement than careful positioning of replacement towers.
At first I couldn't understand why you chose QWE as placement keys, instead of just having the player click the mouse on the tower icon, but then with the pace of the game, I understood it flows much better with immediate placements.
Shaders and music are nice too. Overall aesthetic feels great. I love the retro 80's mainframe vibe.
Great entry.