Release 1.3

• Conditional attributes
  https://github.com/Netflix/fast_jsonapi#conditional-attributes
• Conditional relationships
  https://github.com/Netflix/fast_jsonapi#conditional-relationships
• Sparse fieldsets support ⭐
  https://github.com/Netflix/fast_jsonapi#sparse-fieldsets
• Better Control Over Collection Serialization
  https://github.com/Netflix/fast_jsonapi#collection-serialization