References Let's get back to the Group. Ideally, a group should have members, and Charlatan allows you to reference one record from another one. You can do that with the @name notation, where name is a fixture name.
Let's add a fixed owner to the group:
user:
admin_1:
first_name: 'William'
last_name: 'Wallace'
group_id: '@group_1'
user_{1..10}:
first_name: 'Bob {current}'
last_name: 'The sponge'
group_id: '@group_2'
group:
group_1:
name: admin
group_2:
name: reader