FactoryBot.define do sequence :generic_email do |n| "generic_email_#{n.to_s.rjust(3, '0')}@example.com" end sequence :generic_username do |n| "user_#{n}" end factory :user do username { generate(:generic_username) } email { generate(:generic_email) } full_name { "MyString" } password_digest { "MyString" } admin { false } end end