Ask HN: How to develop software that could be run on a spaceship?

How to create a software that is so reliable and stable that it would use very limited processing power and recover from all(most all) failures. So I thought the one true challenge for software is when it has to run on a spaceship!

What tools and development strategies could one use today to achieve such a goal?

(Note: This is not about spaceship software in particular but how "lessons learned" from spaceship software development could be valuable for non-spaceship software)