(system s)

Create a system.

Takes a map with the following elements:

A keyword to refer to this system later.
Namespaced symbol of the system’s function. If :process-fn is provided, :process can be omitted. However the system won’t be serializable in this case.
System’s function itself. :process-fn will be resolved automatically if :process is provided.
Components this system will read.
Components this system will read and write.

Components not specified in either :reads or :writes won’t be accessible to the system.