Day Index

A comprehensive registry of all 100 engineering patterns, failure modes, and governance lenses.

Series ProgressDay 74 of 100

Lens:

Day	Title	Failure Prevented	Lens	Domain
001	The Sanctity of the Environment	Dependency Hell	Reproducibility	MLOps
002	Version Control for Data & Code	Silent Drift	Reproducibility	Data Infra
003	Containerization Basics (Docker)	Environment Skew	Production	Infra
004	Unit Testing for Data Science	Silent Logic Failure	Safety	QA
005	Experiment Tracking & The 'Zombie Model' Problem	Zombie Models	Reproducibility	MLOps
006	Exploratory Data Analysis (EDA) & Profiling	Digital Redlining	Safety	Data Science
007	Feature Engineering & Selection	Data Leakage	Reproducibility	Data Science
008	Baseline Models & Benchmarking	Complexity Tax	Governance	Data Science
009	Evaluation Metrics for Business	Metric Misalignment	Production	Data Science
010	Model Validation Strategies	Temporal Leakage	Security	Data Science
011	Algorithmic Fairness: Auditing & Mitigation Pipelines	Deployment of Discriminatory Models	Ethics	Model Evaluation
012	Explainable AI (XAI): From Black Box to Glass Box	Stakeholder Rejection (The Black Box Problem)	Human Factors	Model Evaluation
013	Data Privacy & Anonymization: The Toxic Waste Model	Regulatory Non-Compliance (GDPR/CCPA)	Governance	Data Engineering
014	Model Cards: The 'Nutrition Label' for AI	Model Misuse & Context Collapse	Ethics	Governance
015	The Generative Shift: LLMs, APIs, and Unit Economics	Architectural Mismatch & Cost Blowout	Security	LLMs / Generative AI
016	Cloud Infrastructure for AI: Compute, Cost, and Carbon	Bill Shock & Resource Starvation	Sustainability	Infrastructure
017	CI/CD for ML: The Death of 'It Works on My Machine'	Manual Deployment Errors	Security	MLOps
018	Data Lineage: The Chain of Custody for AI	The 'Orphan Model' (Provenance Collapse)	Governance	Data Engineering
019	The ROI of AI: Translating F1 Scores to P&L	Project Cancellation (The 'Science Project' Trap)	Ethics	Strategy
020	Phase 1 Capstone: The 'End-to-End' Production Pipeline	Integration Hell (Fragmented Architecture)	Reproducibility	Orchestration
021	The LLM API Landscape (OpenAI, Anthropic, Mistral)	Vendor Lock-in	Governance	MLOps
022	Prompt Engineering I: Structure & Context	Garbage In, Garbage Out (Ambiguity)	Human Factors	MLOps
023	Prompt Engineering II: Reasoning (CoT & ReAct)	Logic Hallucination	Safety	LLMs
024	Structured Outputs (JSON Mode & Function Calling)	Pipeline Breaks (Parser Errors)	Security	MLOps
025	Building Conversational Memory: State Management Patterns	Conversational Amnesia (Statelessness)	Privacy (Right to be Forgotten)	Application Layer
026	Evaluating Generative Models (Beyond Accuracy)	The 'Vibe Check' Trap	Human Factors	MLOps
027	Automated Evaluation (LLM-as-a-Judge)	Scaling Bottlenecks (The Human Review Queue)	Governance	MLOps
028	Embeddings & Vector Space	The Synonym Gap (Keyword Mismatch)	Ethics (Algorithmic Bias)	RAG / Search
029	Vector Databases (Infrastructure)	Latency Spikes (The O(N) Bottleck)	Security (Tenant Isolation)	Infrastructure / RAG
030	RAG Architecture I: The Data Pipeline & Chunking Strategy	Context Fragmentation	Governance (Data Lineage)	RAG / Data Engineering
031	RAG Architecture II: Hybrid Search & Re-ranking	Semantic Drift (The Specificity Trap)	Reliability	RAG / Search
032	RAG Architecture III: Grounding & Citations	Hallucinations masked as facts	Ethics	LLMs
033	Automated Evaluation (The RAG Triad)	Vibes-based Deployment	Governance	MLOps
034	Advanced Query Transformations	The Zero-Result Problem	Human Factors	LLMs
035	Semantic Caching (The Cost Firewall)	Bill Shock & Latency	Security	MLOps
036	Observability for Chains (Tracing)	Black Box Debugging	Privacy	MLOps
037	Adversarial Defense (Prompt Injection)	The DAN Attack	Security	LLMs
038	Privacy Engineering: PII Masking	Data Leaks to Third Parties	Governance	Security
039	Vector Database Operations (Scale)	Metadata Explosion	Security	Data Infra
040	The Fine-Tuning Pivot (Build vs. Buy)	Over-engineered RAG	Business Strategy	MLOps
041	Evaluation Driven Development (EDD): Escaping Regression Roulette	Regression Roulette	Safety	LLMs
042	Shadow Deployment: The Art of Silent Validation	Big Bang Failures	Governance	MLOps
043	Feature Stores: The Time-Travel Problem	Training-Serving Skew	Reproducibility	Data Infra
044	Model Monitoring: Beyond 'Is it Up?'	Silent Performance Decay	Ethics	MLOps
045	Data Quality Contracts: The First Line of Defense	Garbage In, Disaster Out	Governance	Data Infra
046	Model Calibration: The honesty of AI	Overconfidence	Safety	MLOps
047	Orchestration: Taming the Cron Job Sprawl	The Cron Job Sprawl	Governance	MLOps
048	Local LLMs: The Air-Gapped Intelligence	Data Sovereignty Violations	Privacy	LLMs
049	Error Analysis: The feedback loop that kills stagnation	Stagnation	Ethics	MLOps
050	The Mid-Series Capstone: The 'Production-Ready' Check	Tutorial Knowledge	Leadership	System Architecture
051	Mechanistic Interpretability: Circuit Analysis & Model Surgery	Superficial Explanations	Safety	LLMs
052	Counterfactual Analysis: The 'What If' Engine	Actionable Recourse Failure	Human Factors	MLOps
053	Faithful Explainability: Probing & Lie Detection	Post-Hoc Rationalization	Safety	LLMs
054	Fairness Auditing: Group Metrics & The Impossibility Theorem	Discriminatory Deployment	Ethics	MLOps
055	Bias Mitigation: Re-weighting & Constraints	Baked-in Prejudice	Legal	MLOps
056	Automated Documentation: The Dynamic Model Card	Documentation Drift	Governance	MLOps
057	Content Provenance & Watermarking (C2PA)	Deepfake Liability	Ethics	GenAI
058	Data Poisoning Defense: Detecting the Trojan Horse	The Trojan Horse	Security	ML Security
059	Machine Unlearning: The Right to be Forgotten	Compliance Gridlock	Privacy	MLOps
060	The White Box Capstone: The Audit Defense	Regulatory Shutdown	Leadership	MLOps
061	The ReAct Pattern: Bounding Reasoning and Execution	Action Hallucination	Safety	Agentic Systems
062	Robust Tool Definitions: Schema Engineering as Prompting	API Crashes	Security	Agentic Systems
063	The Context Window Economy: Engineering Memory Management	Context Overflow	Privacy	Agentic Systems
064	Sandboxing Code Execution: The RCE Defense	Remote Code Execution	Security	Agentic Systems
065	Human-in-the-Loop: Engineering the Authorization Gate	The $10k Mistake	Human Factors	Agentic Systems
066	Agentic Search: Look-Ahead Safety via Tree of Thoughts and MCTS	Linear Blindness	Safety	Agentic Systems
067	Multi-Agent Handoffs: Engineering the Router Pattern	Context Bleed	Ethics	Agentic Systems
068	Agent Observability: Tracing the Loop and Preventing 'The Infinite Spend'	The Infinite Spend	Operations	Agentic Systems
069	Evaluating Agents: The Necessity of Trajectory Analysis	Right Answer, Wrong Method	Safety	Agentic Systems
070	The Agentic Capstone: Architecting the Autonomous Analyst	Toy Agents	Leadership	Agentic Systems
071	Multi-Agent Orchestration: Graph-Based Control	The Infinite Loop (Cyclic Dependency)	Safety	LLM Orchestration
072	State Management & Persistence: Time-Travel	The Amnesiac Agent	Governance	MLOps
073	AI FinOps: Token Routing & Budgeting	The $10k Weekend	Sustainability	FinOps
074	Knowledge Graphs for RAG: GraphRAG	The Connecting-the-Dots Failure	Ethics	RAG & Data Retrieval
075	Multimodal Pipelines: Vision & Audio	Context Blindness	Privacy	Multimodal RAG
076	Alignment Engineering: Direct Preference Optimization (DPO)	Tone Deafness (Correct but Unusable Output)	Safety	Model Alignment
077	Generative UI: Beyond the Chatbot	Chat Fatigue (Text-Forced Workflows)	Human Factors	AI UX / Frontend
078	Enterprise Governance: Access Control Lists (ACLs) for RAG	The Salary Leak	Security	Governance & Retrieval
079	Strategic Architecture: Build vs. Buy vs. Fine-tune	Resume-Driven Development	Leadership	AI Strategy
080	Capstone II: The Data Flywheel	Stagnant Intelligence	Ethics	MLOps & Continuous Learning
081	Inference-Time Compute: Architecting the Thinking Budget	The Intelligence Ceiling	Transparency	LLM Architectures
082	Knowledge Distillation: Breaking the Forever Cost	The Forever Cost	Ethics	Model Optimization
083	Structured Generation II: FSM-Guided Decoding	Hallucinated Structure	Security	LLM Inference
084	Engineering for High-Stakes: Medical & Legal Domains	The Malpractice Lawsuit	Ethics	High-Stakes AI
085	The Co-Pilot UX Pattern: Engineering Human Agency	The Autopilot Fallacy	Human Factors	AI UX & Integration
086	Organizational Design: Architecting the AI Platform Team	Siloed Engineering	Leadership	Platform Engineering
087	Global Compliance Engineering: Operationalizing the EU AI Act	Regulatory Fines	Governance	Compliance Engineering
088	Constitutional AI: Architecting Scalable Oversight	Whac-A-Mole Safety	Safety	Alignment
089	Continuous Red Teaming: Architecting the Immune System	Day 2 Vulnerabilities	Security	AI Security
090	Crisis Simulation: Architecting the War Room and the Kill Switch	Panic	Leadership	Incident Response