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Architecture Decision Records

Architecture Decision Records capture decisions that affect the long-term structure, operation, security, or rebuildability of Atlas.

When to Create an ADR

Create an ADR for decisions about:

  • Infrastructure management approach.
  • Service topology.
  • Storage layout.
  • Deployment model.
  • Backup and recovery model.
  • Security and trust boundaries.
  • Tooling choices with long-term maintenance impact.

Small implementation details do not need ADRs unless they establish a precedent.

Naming Convention

Use a four-digit sequence number and a short lower-case slug:

0001-infrastructure-as-code.md
0002-example-decision.md

Do not renumber existing ADRs.

Required Sections

Each ADR should include:

  • Status
  • Context
  • Decision
  • Consequences
  • Alternatives considered

Accepted ADRs remain part of the historical record. If a decision changes, create a new ADR that supersedes the earlier one.