The backend of the Metanet that is comprised of complexity and code, allowing the Metanet to exist.

Seamspace is explored and understood primarily through code, much of it raw binary information. Seam-hackers, programmers, network engineers, and other skilled users interface with it via special programs and hardware (especially a Cerulean Key, a special sort of network card/processor).

There are different areas of Seamspace, and users can create their own areas as well. The main area is referred to as the Atrium, and it is just a huge expanse of code that can be manipulated to open up paths to new areas. Using special code, users can create smaller programs to run in and through the Seamspace. The most common is a shared chat program just called "Chat." It has an ASCII feline logo (a pun on the Galdish word for "cat" being "chat"). The next most common programs are all games and "doors," or paths to outside Seamspace, allowing users access to other computers, sometimes in other realities. Search engines use up a lot of power in the Seamspace.

Users of Seamspace have a large library of commands they can use, most of them derived from common computing commands:

grep
run
open
cd
help
close
del
copy
cut
paste
save
undo
lock

And many other common programming and OS commands.