# Introduction
A business logic addon should follow the conventions and guidelines used to develop Soffid IAM.
It must be composed of:
1. Hibernate entities and mappings.
2. DAOs to access those hibernate entities. They must contain transformation methods to build value objects from entities and vice versa.
Service objects to manage value objects.
3. EJBs that wrap access to service objects. They are responsible for security access control. They must be Stateless Session Beans with Container transaction management.
4. Authorizations descriptor.
5. Spring descriptor.