Metrici uses nodes to define structures and behaviour. It uses a set of standard nodes to define the basic capabilities of the application.
There are three sets of standard nodes:
- System nodes are referenced internally by the node controllers, or are required by nodes which are. These have fixed definitions: their node and node version identifiers are fixed, they are always frozen, and there is only ever one version.
- Standard libraries are not referenced internally the node controllers, but provide additional capabilities built on top of the system nodes.
- User nodes provide a node view of user definitions.
You can think of the system nodes as "kernel data" that are part of the underlying Metrici software. The standard libraries are application data that nearly all solutions will need.
The definitive documentation of standard nodes is held on the nodes themselves. The following sections give an overview of the ones relevant to development.