arch-decisions-exploration-edited.md

Exploration: Engineering Architecture Decision-Making Frameworks

Industry Patterns and Precedents

Based on research across technology organizations, three distinct approaches have emerged for managing architecture decision-making, each with documented successes and failures:

1. Advisory Architecture Process (Stripe/Netflix Model)

Stripe's approach:

• Architecture decisions are made by the implementing team
• A group of senior engineers (Staff+) provides feedback and guidance
• No formal approval is required, but teams are expected to incorporate feedback
• Escalations go to engineering leadership only for disagreements on critical decisions

Netflix's "Freedom and Responsibility":

• Engineers make decisions within their sphere of responsibility
• Context is shared broadly through documentation and RFCs
• "Keeper test" ensures high-performing individuals drive decisions
• Strong emphasis on documentation to enable distributed decision-making

2. Federated Architecture Councils (Amazon/Google Model)

Amazon's "Two-Pizza Team" model:

• Each service team owns their architecture decisions
• "Well-Architected Framework" provides consistent evaluation criteria

Google's approach uses Technical Lead Networks:

• Technical Leads (TLs) in each area coordinate architecture decisions
• Area-specific expertise concentrated in dedicated roles
• Regular "Architecture Review Committee" for company-wide decisions
• Strong emphasis on written design documents and peer review

3. Centralized Architecture Authority (Traditional Enterprise)

Microsoft's historical model (pre-cloud transformation):

• Central architecture board approves all significant decisions
• Detailed architecture standards and governance processes
• Technology choices limited to approved stack
• Strong emphasis on consistency and risk management

Traditional enterprise approach seen at companies like IBM, Oracle:

• Enterprise architects define technology standards
• Project approval gates require architecture compliance
• Centralized technology evaluation and vendor management
• Risk mitigation prioritized over speed

Framework References from Established Strategy Resources

Architecture Decision Records (ADRs)

Michael Nygard's pattern, widely adopted across industry:

• Lightweight documentation of architecture decisions
• Captures context, options considered, and rationale
• Immutable record enabling future teams to understand reasoning
• Successfully implemented at ThoughtWorks, Spotify, and numerous startups

Technology Strategy Patterns (Eben Hewitt)

The "Architectural Decision Authority" pattern:

• Clearly defined decision rights at different organizational levels
• Escalation paths for cross-cutting concerns
• Balance between autonomy and coordination
• Specific implementation guidance for different organization sizes