© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. © 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. Shiro Seike (@seike460) Principal Engineer / Evangelist Fusic Co., Ltd. Architecture as Steering On-Ramp to AI-DLC A W S S U M M I T H O N G K O N G 2 0 2 6 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. Principal Engineer / Evangelist — Fusic Co., Ltd. (Fukuoka, Japan) JAWS DAYS 2026 Chair · JAWS-UG Fukuoka (AWS User Group Leaders) AWS Community Builder (Serverless) 2025 Japan AWS Top Engineers (Services) Shiro Seike (@seike460) 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. AI crosses boundaries the compiler can’t see Encode architecture as Steering — your on-ramp to AI-DLC v2 Kiro, and since this June, Claude Code Take home only two things 1 Diagnosis 2 Prescription 3 On-ramp 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. © 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. 1 · Diagnosis The build is green. The boundary broke. 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. C H A P T E R 1 · D I A G N O S I S The compiler said yes. The boundary said no. 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. © 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. “I reached for a bigger model first” A bigger model won’t fix a boundary you never wrote down. 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. © 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. 2 · Prescription From pain to proof — make the rules executable. 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. C L A U D E . M D — T R A N S L A T E D E X C E R P T Steering = the rules the agent can’t infer (not a map — a lens) 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. D E P E N D E N C Y - C R U I S E R · R U N S I N C I Pillar 1 / Clean Architecture — dependencies point inward, and CI enforces it 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. S T R U C T U R A L G U A R D R A I L + T W O - L A Y E R D E F E N C E Pillar 2 / Hexagonal Ports — zero runtime deps (a guardrail, not the whole proof) 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. F A S T - C H E C K P R O P E R T Y · S T A T E M A C H I N E Pillar 3 / Domain-Driven Design — one example can lie,so I generate 100 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. dep-cruiser: the first column, not the whole matrix Pillar dep-cruiser Type / Lint Fitness / Property test AI review Clean ✓ CI gate today partial — — Hexagonal ✓ direction — deps:{} guardrail PASS guard hook DDD invariants — out of reach — fast-check property PASS semantic rules 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. Steering OFF Steering ON THE SAME prompt — Steering off vs on 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. 1 CLAUDE.md 6 steering files 1 command (perfect) one entry point it points at the steering one concern per file read in one sitting type-check · depcruise · tests one green It scales: one set of rules, every package 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. © 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. 3 · On-ramp AWS and I converged on the same three pillars. 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. architecture-review + domain-modeling skills (AI-DLC v2, MIT-0) Kiro target: 8 personas, incl. a standalone architecture-reviewer Your architecture gets an official home Kiro, and since this June, Claude Code I enforce them by hand. AWS ships the same ones. 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. A W S L A B S / A I D L C - W O R K F L O W S V 2 · P R O C E S S - C H E C K E R . J S “self-verifies deterministically” = a real Node script 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. v2 = active dev branch; stable is main Three honest phases — and where the gaps are INCEPTION CONSTRUCTION fans out per unit OPERATIONS “(future stages)” — not yet 

© 2026, Amazon Web Services, Inc. or its affiliates. All rights reserved. Today (5 min) write one boundary as a Steering rule in CLAUDE.md This week add one dependency-cruiser rule to CI — green, then red on a violation Real work clone fusic/architecture-as-steering, then adopt awslabs/aidlc-workflows (main = stable) Your on-ramp — three honest steps github.com/fusic/architecture-as-steering 

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