Episode 279 - Residuality Theory with Barry O’Reilly | Bullet Points

Key Takeaways

• Residuality Theory states that randomly simulating stress produces a more resilient architecture.
• The theory is based on scientific findings from complexity research, particularly the work of Stuart Kauffman.
• Architectures are tested and improved through stressors (factors causing strain).
• The goal is an architecture that can survive unknown future requirements.
• The method requires shifting thinking from correctness to criticality.
• An architecture reaches a point of “criticality”, where it becomes robust against unknown changes.

Core Questions Addressed

• How can you develop architectures that survive unknown future requirements?
• How can you identify and use stressors to improve architecture?
• What is the scientific foundation of Residuality Theory?
• How does this approach differ from classical risk management?
• How can you tell whether you’re on the right track with this method?
• How does the theory relate to other architectural approaches like YAGNI?

Glossary of Key Terms

• Stressor: A factor that puts the architecture under stress and may cause it to break.
• Criticality: The state of an architecture in which it is robust against unknown changes.
• Residue: An architectural component that survives certain stressors.
• Attractor States: A limited number of possible states a complex system can assume.
• Stressor Analysis: A tool for systematically analyzing stressors.
• Random Boolean Networks: A mathematical model for describing complex systems.

Residuality Theory presents a novel, scientifically grounded approach to developing robust software architectures. It requires a fundamental shift in how we design architectures but promises systems that can better handle unknown future requirements.