Learning path · Trilha
Security & Resilience
Zero Trust, observability, chaos engineering and DR — building systems that withstand failure and attack.
The path· 8
- 1Advanced 10 minCognito Multi-Region: Migrating Identity to High AvailabilityAuthentication is critical infrastructure — a regional Cognito failure brings down the entire user journey. With Cognito multi-Region replication now available, there is a concrete path to elevating the identity plane to the same resilience level we already demand from databases and queues. In this article, I document the migration journey, the architecture decisions, and the risks that need active management.
- 2Advanced 8 minScalable User Search with Amazon Cognito: A Deep-Dive AnalysisAmazon Cognito excels at authentication, but its user-listing API was never designed for high-frequency search against large user pools. In this article, I analyze how to build a scalable search layer on top of Cognito, the failure modes that emerge when you ignore native API limits, and the real trade-offs between eventual consistency, data privacy, and operational cost.
- 3Advanced 9 minPostmortem: When AI Meets Resilience — AWS Resilience Hub and SREAWS Resilience Hub gained generative AI capabilities for failure mode analysis and runbook generation — a change that looks incremental but redefines how SRE teams operate in production. In this retrospective, I analyze what this evolution means in practice, where it fails, and how to integrate these tools into financial-grade systems without creating new fragile dependencies.
- 4Advanced 11 minAWS WAF and AI Bot Traffic Monetization: A Technical ReviewAWS WAF has gained native capability to identify and route AI bot traffic — a shift that turns a defensive tool into a revenue control point. In this article, I analyze what the feature actually delivers, where it falls short, and how to integrate it safely in financial-grade architectures.
- 5Advanced 9 minADR: Replacing SMS OTP with Silent Authentication in CognitoSMS OTP is simultaneously the most widely deployed authentication mechanism and one of the weakest: vulnerable to SIM swap, SS7 interception, and social engineering, with only ~80% completion rates. This ADR examines the decision to replace or complement SMS OTP with network-silent authentication via Vonage integrated into Amazon Cognito's CUSTOM_AUTH flow.
- 6Expert 11 minRansomware Recovery Patterns on AWS: A Technical ReviewRansomware remains the highest-financial-impact threat vector in enterprise environments — and AWS provides solid technical primitives to build real resilience. In this analysis, I examine the recovery patterns published by the AWS Architecture Blog through the lens of someone who has operated DR plans in regulated financial environments. The result is an honest view: where these patterns deliver real value, where operational gaps exist, and what you need to add for them to hold under pressure.
- 7Expert 9 minOIDC Session Metadata and Zero Trust: An Architecture Decision RecordSession metadata support in Sign in with Google opens a genuine window for continuous, signal-driven adaptive access — not just at login time. In this ADR, I analyze the architectural forces, options considered, and the decision I would make in a high-criticality financial system integrated with AWS.
- 8Expert 8 minAI Agents for Security and DevOps: Productivity or Risk?AWS launched frontier agents for security testing and cloud operations, opening a real debate about how far AI autonomy can go in regulated environments. This article compares four deployment patterns — fully autonomous agent, semi-autonomous with human approval, assisted (copilot), and deterministic pipeline — using concrete criteria of risk, cost, latency, and compliance.
Deep-dive studies
guideLoop Engineering: designing the loops that guide AI agentsThe bottleneck in AI agents has shifted from the prompt sentence to the loop design: trigger, topology, verifier, and stop rules. This guide teaches loop engineering fundamentals — from the base ReAct loop to a pattern catalogue — with real examples from my own system and a step-by-step guide for engineering any loop safely.playbookPlaybook: 5 AI Architecture Shifts — and what to do about each oneWhat was advanced in 2025 became default in 2026: the bottleneck moved past the prompt, agents went to managed production, MCP standardized tooling, security became layered, and token FinOps entered the roadmap. This playbook maps each shift to concrete actions — for people building systems, not demos.guideInside AI Agents (1/3): Anatomy and the Reasoning LoopA technical lesson for developers and architects who hear 'AI agent' every day but want to truly understand what differentiates an agent from a plain LLM, a fixed pipeline, or simple RAG. We cover the full anatomy — model, tools, memory, planner — and the ReAct loop step by step with a concrete example. No hype; real trade-offs.guideInside AI Agents (2/3): Architecture Pattern Catalog — from ReAct to Multi-AgentThe second lesson in the series maps the full catalog of AI agent architecture patterns: from single-agent loops (ReAct, Reflexion, Plan-and-Execute) to multi-agent orchestration, covering memory as an architecture decision, guardrails, and human-in-the-loop. The goal is to give the architect a precise vocabulary to choose — and justify — the right pattern for each problem, without falling into classic anti-patterns.guideInside AI Agents (3/3): Agents in Production on AWS with Bedrock AgentCoreThe third and final part of the series descends the elevator to the technical floor: how to run an AI agent in production on AWS using Amazon Bedrock AgentCore. We cover the full component map (Runtime, Gateway, Memory, Identity, Observability), model selection by cost/latency/reasoning, security with guardrails and session isolation, and FinOps to keep real costs under a few dollars per month.adrADR: Automated Policy Refinement in Bedrock GuardrailsThe new iterative refinement and ambiguity reduction workflows in Bedrock Guardrails Automated Reasoning checks reduce the manual burden of maintaining formal policies — but introduce non-trivial architectural decisions around governance, policy lifecycle, and CI/CD pipeline integration. In this ADR, I analyze the context, options considered, and real consequences of this decision in regulated financial environments. Open source to explore
aws-event-driven-finops-platformEvent-driven AWS banking reference architecture with FinOps, security, and a live frontend.aws-agentic-ai-reference-architectureAWS reference architecture for production agentic AI — security, observability, and DevSecOps.DeskbuddyESP32 touchscreen smart desk dashboard — firmware, web UI, and browser installer in one repo.solution-architecture-mcp-toolkitBilingual MCP toolkit for ADRs, threat modeling, and governed Well-Architected reviews.bedrock-agent-starterProduction-shaped Amazon Bedrock agent starter — tools, IaC, and evals in 30 minutes.aws-ai-reference-architecturesSix AWS AI reference architectures — diagrams, IaC skeletons, and Well-Architected analysis.