After working on the concept for the game for two years, Mario "ehmprah" Kaiser built a proof-of-concept version of Coregrounds for half a year and released it by the end of 2015. Together with a small community the core gameplay was evolved and battle-tested before Mario teamed up with Dominic "DNKpp" Koepke to level up the technology behind Coregrounds. This current version was released on Steam in April 2018. Due to performance issues, the mobile versions weren't released, a rework of the client graphics was started but not completed. Ultimately, the devs weren't able to support this project the way it deserved, but maybe the community will!

It's now open source on GitHub.