Decision records are value preservation.
Decisions outlast code
Code gets refactored, rewritten, and deleted. Roadmaps change quarterly. Team members leave. But the reasoning behind a well-documented architectural decision remains valuable for years.
The anatomy of a useful ADR
- Title: A short, descriptive name
- Context: What situation prompted this decision? What constraints existed?
- Decision: What was decided, clearly and concisely
- Alternatives considered: What other options were evaluated? Why were they rejected?
- Consequences: What are the expected benefits and trade-offs?
- Status: Proposed, accepted, deprecated, or superseded
Decision records as organizational memory
Individual memory is unreliable and non-transferable. Decision records create organizational memory that survives team changes: new members read the history, incident responders check intent, planners review past decisions to avoid repeating mistakes.
An ADR costs an hour to write and saves weeks of future investigation. The return on investment is among the highest of any engineering practice.