Nuclear powered robots that don't need to recharge. Forked from Buggi's Nuclear Bots and changed to have a more balanced formula, not have 3x the speed of normal bots, fire immunity, and some acid resistance for construction bots. Finally a use for all that Uranium that piles up! The recipie was scaled to require as much energy as a normal bot would use in 21 years - about the same time that a nuclear submarine reactor core lasts.
You may have crash-landed on this planet, but it seems you weren't the first to settle here. Abandoned Ruins adds ruins to world generation for you to explore and build into your own base, but be careful... Just because the ruins are long since abandoned, their defences might not be as dormant.