Internally we’ve been using Linux for building the game for a long time, but we hesitated doing a release for Linux because there are so many Linux distributions and the resulting package dependencies and other issues can create an installation headache. However now is the time to test it anyway, so please download it from the Download page if you run a 64-bit Linux, and see if it works!
Any feedback is welcome, either as a comment here or on the sub-reddit forum!
Please make sure you read the README.Linux in the download tar-ball. A few package dependencies are listed there.