System design judgment for engineers who build production systems.

Premium long-form articles on architecture trade-offs, failure modes, and the operational thinking that separates senior engineers from principal engineers.

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Cache-Aside: Why It Works, Where It Breaks

Cache-aside is the default read optimization in most production systems because it preserves source-of-truth ownership. It also hides a set of failure modes that surface under misses, invalidation races, and stale reads.

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Failure-first, not diagram-first

Every article opens with what breaks. Production realism is the default, not a footnote.

Judgment, not pattern memorization

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How Systems Work

Build intuition for how production systems behave under load.

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Components & Patterns

Study the components and patterns that shape reliable systems.

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System Design

Compare architecture trade-offs before they become outages.

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Engineering Judgment

Strengthen the judgment behind roadmap and scaling decisions.

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AI Systems

Understand AI infrastructure with the same production rigor.

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LATEST INSIGHTS

Short notes on AI, infrastructure, and industry shifts.

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March 21, 2026

Karpathy's 'No Code December' and the Real Shape of AI Leverage

Karpathy's 'No Code December' matters less as a literal workflow prescription and more as a signal: engineers are shifting from typing implementation details toward supervising systems that produce them.

7 min readAi AgentsCodingIndustry

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March 18, 2026

Claude Code vs Codex: The Real Difference Is Workflow Shape

The sharpest difference between Claude Code and Codex is not raw intelligence. It is workflow shape: how each system scopes context, moves through a repo, and helps engineers trade speed against certainty.

8 min readAi AgentsCodingLlm

Related deep dive OpenAI Codex Agent Architecture

March 15, 2026

What OpenAI Codex Reveals About Agent Architecture

The most interesting thing about modern coding agents is not that they generate code. It is that they combine search, planning, execution, and verification into a coherent operator loop that behaves more like a constrained teammate than a chatbot.

9 min readAi AgentsInfrastructureIndustryLlm

Related deep dive OpenAI Codex Agent Architecture

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What OpenAI Codex Reveals About Agent Architecture

9 min readAi AgentsInfrastructureIndustryLlm