Developer: Brian Prescott

Brian Prescott is a homebrew programmer who wrote Vault Assault, released on cartridge in 2001. Based on the arcade game Space Zap, it puts you in a vault in the middle of the screen, fighting off ships from all four sides as the pace keeps rising. He sold every copy he brought to the 2001 Classic Gaming Expo and made the source code public.
Defend the vault below, in your browser.