Version 0.4.8 was released on August 30th and as usual, they only provide pre-built versions for Mac and Windows. For Linux gamers, you will need to either grab an updated package from an outside repository or compile it yourself. Hopefully this will be a good case for Snap and Flatpak to get it to users easily.
There's a ridiculous amount of improvements with this release with tons of UI improvements, vast improvements to the multiplayer capabilities, extensive AI improvements, game rules can be modified, the addition of more playable species along with tons of balance updates and bug fixes. You can see an extensive look at the changes here.