This article describes the original AWS Well-Architected Framework pillars as they were presented when this post was written, and introduces elasticity. AWS has since updated the framework; check the current documentation before applying its guidance.

The original framework described five pillars:

 1. Security
 2. Reliability
 3. Performance efficiency
 4. Operational excellence
 5. Cost optimization

AWS later added sustainability as a sixth pillar. Refer to the current AWS Well-Architected Framework for up-to-date principles.

Security - Design Principles

The security pillar concerns protecting information, systems, and assets while delivering business value through risk assessment and mitigation.

1. Implement a strong identity foundation
2. Enable traceability
3. Apply security at all layers
4. Automate security best practices
5. Protect data in transit and at rest.
6. Prepare for security events.

Reliability - Design Principles

Reliability pillar includes the ability of a system to recover from infrastructure or service disruptions, dynamically acquire computing resources to meet demand, and mitigate disruptions, such as misconfigurations or transient network issues.

1. Test recovery procedures
2. Automatically recover from failure
3. Scale horizontally to increase aggregate system availability
4. Stop guessing capacity
5. Manage change through automation

Performance Efficiency - Design Principles

Performance efficiency pillar includes the ability to use computing resources efficiently to meet system requirements and to maintain that efficiency as demand changes and technology evolve.

1. Democratize advanced technologies
2. go global in minutes
3. use serverless architecture
4. experiment more often
5. mechanical sympathy

Operational Excellence - Design Principles

The operational excellence pillar concerns running and monitoring systems to deliver business value and continually improving supporting processes and procedures.

1. Perform operations as code
2. Annotate documentation
3. Make frequent, small, reversible changes.
4. Refine operations procedures frequently
5. Anticipate failure
6. Learn from all operational events.

Cost optimization - Design Principles

The cost optimization pillar concerns avoiding unnecessary costs while meeting requirements.

1. Adopt a consumption model.
2. Measure overall efficiency.
3. Stop spending money on data center operations.
4. Analyze and attribute expenditure.
5. Use managed services to reduce cost of ownership.

Elasticity

Elasticity is the ability to acquire and release resources as demand changes. Automated horizontal scaling is one way to implement it, but elasticity can involve other resource types and scaling policies. A design should balance responsiveness, reliability, and cost.