Part of Stem. This page defines the Group blob.

A Group is a signed permanode: its CID is the group's id, its signer is the group's owner and permanent admin, and its membership is whoever holds a live grant on it.

Fields

The schema extends blob.

field	type	required	meaning
`type`	literal `Group`	yes	Blob type tag.
`nonce`	bytes	yes	At least 16 random bytes, so two groups by one owner never share a CID.
`label`	string, at most 512 characters	no	A public, immutable name.

Rules

A Group carries no members. Members are added by a Grant whose subject is the group and whose audience is the member, at read; a grant at admin lets the member manage others. A group is used by naming it in an audience. Removing an admin is done by rotating: create a new Group, re-grant the wanted members, repoint the audiences. A group is a blob, not a resource: it has no node, no parent and no state, and it is always public, since it reveals nothing but a nonce and a label. The team's phrase for this design was "a permanode per space whose admins are permanent"; here every space's root plays that role implicitly, and Groups exist for sets of people that cut across spaces.

Today (HM24)

Nothing. Groups as document owners were removed around 2024; the roadmap wants them back as a way to grant to several keys at once.

Example

{
  "type": "Group",
  "signer": {"/": {"bytes": "7QEE...Starlight"}},
  "sig": {"/": {"bytes": "..."}},
  "ts": 1759910400000,
  "nonce": {"/": {"bytes": "Kq8b1xZ2tV4nQ7pR9sL0wE3y"}},
  "label": "Editors"
}

Fields

Rules

Today (HM24)

Example

See also