It is a mini-game, that I created as a teen, called "Atomix," written in BASIC with a mix of Z80 assembly — some of which I coded myself, while other parts were disassembled from existing games. I put the game in an modern emulator and recorded a screencast. See the video in my linkedin post:

https://www.linkedin.com/feed/update/urn:li:activity:7288665...