1. Why I hate active record
for building business applications

2. It is good option for building shallow webapps server side MVC.

3. But not so good for business logic heavy restful
web services

4. Model class tightly coupled with the database

5. Makes it really difficult to decouple business
logic from framework.

6. Not very extensible - example no pluggable id
generation

7. No support for composite keys

8. No auto-dirty checking / transaction write
behind

9. Limited support for persistence by reachability

10. All this makes it difficult to apply DDD or even
basic OO (SRP)

11. Alternatives - datamapper looked promising
or look beyond ruby :-)

12. Those are my observation based on 5 months
of working with AR and comparing it with the 8
years of working with hibernate.