Self replicating device

There are:

• The Gemstone metamaterial on-chip factories concept
• The (outdated) molecular assemblers concept

Delineations

Adaptivity not a requirement

Self replicating devices are not capable of autonomous evolution.
The "sufficient adaptivity" side in the reproduction hexagon does not need to be fulfilled.
While not fundamentally impossible adding such functionality would pose a greater challenge and greater development effort
but not more benefit. More risk rather. Eventually.

Mobility not a requirement

Self replicating devices are not necessarily capable of autonomous locomotion.
The "replicator mobility" side in the reproduction hexagon does not need to be fulfilled.
They are not necessarily mobile robotic devices.

• The (outdated) molecular assemblers are mobile robotic devices
• The now targeted gem-gum factories are not capable of autonomous motion by themselves.
  Unless one one intentional mots them on a mobile (macroscopic) chassis that is not necessary for their functioning of course.

Omnivorousness not a requirement

The "building block availability" side in the reproduction hexagon does not need to refer to the most fundamental building blocks
that nature has to offer. It does not need to refer to atoms and the simple-most molecules as found lying around in nature.

Especially early stage system will make a lot use of pre-produced atomically precise blocks. E.g. foldamers.
More advanced systems will be capable of processing common liquids and gasses though some of them occurring in the wild.
Like e.g.:

• Components of the air like e.g. carbon dioxide (CO₂).
• Dissolved salts in water (e.g. sodium sulfate Na₂SO_{4>/sub> as a source for sulfur)}
• ...

Related

• Self replication
• Reproduction hexagon
• Bootstrapping
• Exponential assembly