SaaS Users and Roles Model

classDiagram
  class User {
    +String id
    +String email
    +String name
  }
  class Organisation {
    +String id
    +String name
    +String plan
    +invite(email, role) Invitation
  }
  class Membership {
    +String status
    +can(permission) bool
  }
  class Role {
    +String name
    +bool isSystem
  }
  class Permission {
    +String key
  }
  class Invitation {
    +String email
    +DateTime expiresAt
    +accept(user) Membership
  }
  Organisation "1" --> "*" Membership
  User "1" --> "*" Membership
  Membership --> Role
  Role "1" --> "*" Permission
  Organisation "1" --> "*" Role : custom roles
  Organisation "1" --> "*" Invitation