Foust blocks
Foust blocks are smart blocks used to create satellites and other space-based large-scale tools and vehicles. They are named for Becca Foust, an engineer who worked at the Jet Propulsion Laboratory. She made a breakthrough while working as a research fellow that allowed them to easily reform into almost any configuration. They are still used over 2000 years later, though the technology they contain has been significantly upgraded since the first ones used in the 2020s.
Description
Foust blocks come in a variety of sizes, from nanites to much larger blocks, and while they are called "blocks", they come in almost any geometric shape. When they are programmed, they connect to each other using a molecular bond, allowing them to hold together very cleanly and seamlessly. They still maintain their autonomy, however, so if they are ordered to reform, they can disconnect the molecular bond and rearrange themselves according to the program instructions. For more permanent structures, they can be ordered to form into the desired structure and then disable themselves, preventing them from reforming.