userpillar.sls

siteuser:
  dimeshake:
    devs:
      - user1
      - user2
  anothersite:
    devs:
      - user3
      - user4

users.sls

{% if pillar['siteuser'] is defined %}
{% for usr in salt['pillar.get']('siteuser')  %}

# snipped - creation of users, housekeeping for each, etc #

/home/{{ usr }}/.ssh/authorized_keys:
  file.append:
    - sources:
    {% for dev in salt['pillar.get']('{{ usr }}:devs')  %}
      - salt://users/keys/{{ dev }}
    {% endfor %}

{% endfor %}
{% endif %}