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Day 4Level 1 — Core Mental Models

Architecture Decision Records: The Unit of Judgement

Learn: 45 minMap: 30 minDesign: 60 min

Core Concepts (5)

  • 1.An ADR captures: Context → Options Considered → Decision → Consequences
  • 2.Every ADR must list ≥2 options considered — if only one, it's not a decision
  • 3.Consequences include: trade-offs, new risks, operational burden, cost impact
  • 4.ADRs are immutable — supersede, don't edit. History matters.
  • 5.The trade-off axis is the one line that explains what you optimised for

Map to Your Experience

Take one decision from your Day 1 inventory. Write a full ADR for it. What options did you really consider? What were the consequences?

Design Brief: ADR for a Critical Decision

Requirements

  • Context links to constraints and requirements
  • At least 2 options with pros/cons
  • Decision statement is unambiguous
  • Consequences cover: risks, ops burden, cost, new decisions needed
  • Trade-off axis is a single named tension

Constraints

  • Use the ADR template from the pattern library
  • No retroactive justification — be honest about what was known

Must Cover

adr-structureoptions-analysistradeoff-axisconsequences

Trade-off Axis

decision speed vs decision rigour

Referenced Patterns

Competencies Advanced

requirements constraints → L3economics evolution → L2

Ready to Design?

Open this brief in the Design Studio. Your constraints, requirements, and patterns will be pre-filled. Create a Design Record and get AI critique.

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