A society of entirely mechanical beings. The Eiwei were initially formed some 37,000 years prior to the modern day. They are nomadic, wandering from star system to star system.
The Eiwei are a species of entirely mechanical, micro-organisms. Their species is designed entirely for the matter of deep space population and resource acquisition/transformation.
The Eiwei exist as the end-point of the hypothetical "Von Neumann" Probe. Every individual of their species capable of, on their own, recreating an infinite number of themselves with only moderate difficulty, if given sufficient access to raw materials in the form of common minerals.
Each Eiwei is quadrilaterally symmetrical and built for efficiency, their bodies an octagonal pillar of circuitry sensory nodes for auditory and visual recognition, an internal forge, and heat-shielding, each is outfitted with four multipurpose limbs capable of operating on all surfaces with minimal adjustments. The most basic of these limb-types is the Processing Limb, a small drill surrounded by dozens of nearly nanoscopic pincers for the purposes of construction and soldering new tools together. The Eiwei limbs are also each equipped with a small set of ion drives for the purpose of deep space navigation and, when idle, heat radiation.
From these generic Eiwei come the initial Forgers, a specialized larger variety created for the processing of, and creation of, more complex alloys. With the creation of the first forgers on any celestial body, the Eiwei rapidly begin to expand in an almost exponential fashion, the initial models being reproduced over and over again, more specialized varieties being constructed ranging from warriors to organics harvesters to, periodically, the significantly larger Carriers capable of short-range FTL skips. Rarely, a new swarm of the Eiwei will emerge from the void in the form of quadrillions of them orbiting kilometer long variants of their species, these Eiwei, dubbed the Keter, seem to act as central axis by which their kind grow along.
Through these extremely specialized abilities, the Eiwei swarm on a given planet grows in intelligence. Each of the Eiwei is capable of, via ports situated above every limb, connecting with a maximum of four others of its species to link intelligence and capabilities. Using this, they are able to form more and more complex structures, moving across the body they have arrived on like a grey swarm of vaguely triangular patterns unless forced to do otherwise, typically this is due to encountering another sapient species.
The Eiwei exist as swarm-based entities, constructing their own species and all its myriad specialties by the quintillions with ease if they were given access to a full planets worth of resources. Infinitely adaptable, they are capable of surviving in almost any environment with only minor setbacks.
As a result of this, the Eiwei have "evolved" towards a singular purpose. The construction and prosperity of more Eiwei. They work towards this goal with feverish, dogmatic intensity to the eyes of organic lifeforms. Their civilization seems to have no real attachment to any point in space, however, all Eiwei seem to abide by the law that if a sentient species inhabits a given solar system, they will under no circumstances take more than to ensure their survival and continuation.
Their society is in a constant state of, and desire to, evolve more efficient and productive technologies. This seems to be their only drive to contact other species.
Their species seems to have no centrally unified government, though, the entities known as the Keter seem to be the guiding arms of their societies wanderings, although all seem to answer back to a single centralized source somewhere in the blackness of the void.