Architecture Decision Records
Comprehensive patterns for creating, maintaining, and managing Architecture Decision Records (ADRs) that capture the context and rationale behind significant technical decisions.
When to Use This Skill
- Making significant architectural decisions
- Documenting technology choices
- Recording design trade-offs
- Onboarding new team members
- Reviewing historical decisions
- Establishing decision-making processes
Core Concepts
1. What is an ADR?
An Architecture Decision Record captures:
- Context: Why we needed to make a decision
- Decision: What we decided
- Consequences: What happens as a result
2. When to Write an ADR
3. ADR Lifecycle
Templates
Template 1: Standard ADR (MADR Format)
Template 2: Lightweight ADR
Template 3: Y-Statement Format
Template 4: ADR for Deprecation
Template 5: Request for Comments (RFC) Style
OrderCreated { orderId, customerId, items[], timestamp } OrderItemAdded { orderId, item, timestamp } OrderItemRemoved { orderId, itemId, timestamp } PaymentReceived { orderId, amount, paymentId, timestamp } OrderShipped { orderId, trackingNumber, timestamp }
ADR Management
Directory Structure
ADR Index (README.md)
Automation (adr-tools)
Review Process
Best Practices
Do's
- Write ADRs early - Before implementation starts
- Keep them short - 1-2 pages maximum
- Be honest about trade-offs - Include real cons
- Link related decisions - Build decision graph
- Update status - Deprecate when superseded
Don'ts
- Don't change accepted ADRs - Write new ones to supersede
- Don't skip context - Future readers need background
- Don't hide failures - Rejected decisions are valuable
- Don't be vague - Specific decisions, specific consequences
- Don't forget implementation - ADR without action is waste

