SpiceDB is an open source, Google Zanzibar-inspired, database system for creating and managing security-critical application permissions.

SpiceDB

https://authzed.com/docs/reference/schema-lang#subject-relations
```
definition user {}

definition group {
    /**
     * member can include both users and *the set of members* of other specific groups.
     */
    relation member: user | group#member
}
```
how should I write relationship if I want grant group:groupA#member role to all members of groupB in this case?

subject definition has an optional relation:
https://cdn.discordapp.com/attachments/1133959338243928115/1134053889868562472/image.png

and even though it's not documented in `zed` (this is probably something we can improve!) you can do something like this

```
zed relationship create group:1 member group:2#member
```