We’re excited to put out the first post-release update for Terra Nil. This is a small update focusing on some performance improvements, polish, bug fixes, and the much awaited native macOS and Linux builds. We’re also working on some bigger, more exciting changes for upcoming updates that we’re looking forward to sharing with you — more news on that coming later. Note: if you have trouble installing macOS/Linux builds, you may need to restart Steam.
Pretty sure it’s been available for Linux for a long time. I played it on Linux back when it was a prototype on itch.io