Duane M Moody — Notes https://www.dmmoody.com/notes Captured thinking — notes by Duane M Moody. en-us Systems Tell You When They Are Failing https://www.dmmoody.com/notes/systems-tell-you-when-they-are-failing Failures that feel sudden are usually preceded by signals that were ignored. Mon, 23 Mar 2026 12:00:00 GMT https://www.dmmoody.com/notes/systems-tell-you-when-they-are-failing Interfaces Are Where Systems Break https://www.dmmoody.com/notes/interfaces-are-where-systems-break Most failures do not occur inside a component. They occur at the boundary between them. Sun, 22 Mar 2026 12:00:00 GMT https://www.dmmoody.com/notes/interfaces-are-where-systems-break Determinism Is Not Optional https://www.dmmoody.com/notes/determinism-is-not-optional If the same input does not produce the same result, the system cannot be trusted. Fri, 20 Mar 2026 12:00:00 GMT https://www.dmmoody.com/notes/determinism-is-not-optional Drift Is the Real Failure Mode https://www.dmmoody.com/notes/drift-is-the-real-failure-mode Systems rarely fail because of a single mistake. They fail because small deviations are allowed to accumulate. Fri, 20 Mar 2026 12:00:00 GMT https://www.dmmoody.com/notes/drift-is-the-real-failure-mode Reconciliation Is Part of the System https://www.dmmoody.com/notes/reconciliation-is-part-of-the-system If you cannot explain what happened, you do not control the system. Fri, 20 Mar 2026 12:00:00 GMT https://www.dmmoody.com/notes/reconciliation-is-part-of-the-system Not Every Problem Is a Process https://www.dmmoody.com/notes/not-every-problem-is-a-process Treating simple decisions as workflows introduces state, complexity, and failure modes that do not need to exist. Sun, 15 Mar 2026 12:00:00 GMT https://www.dmmoody.com/notes/not-every-problem-is-a-process Constraints Make AI Useful https://www.dmmoody.com/notes/constraints-make-ai-useful AI becomes more useful as constraints become clearer. Without boundaries, output quality degrades quickly. Tue, 10 Mar 2026 12:00:00 GMT https://www.dmmoody.com/notes/constraints-make-ai-useful Architecture Is a Decision Discipline https://www.dmmoody.com/notes/architecture-is-a-decision-discipline Architecture is not documentation. It is the discipline of making and protecting consequential decisions. Sun, 01 Mar 2026 12:00:00 GMT https://www.dmmoody.com/notes/architecture-is-a-decision-discipline Simplicity Requires Understanding https://www.dmmoody.com/notes/simplicity-requires-understanding Simple systems are not shallow. They are the result of deeper understanding applied with restraint. Fri, 20 Feb 2026 12:00:00 GMT https://www.dmmoody.com/notes/simplicity-requires-understanding Shared Libraries Create Hidden Coupling https://www.dmmoody.com/notes/shared-libraries-create-hidden-coupling Shared libraries often introduce dependencies that are harder to see than they are to manage. Tue, 10 Feb 2026 12:00:00 GMT https://www.dmmoody.com/notes/shared-libraries-create-hidden-coupling Overengineering Is a Signal https://www.dmmoody.com/notes/overengineering-is-a-signal Overengineering is rarely a sign of sophistication. It is usually a sign that the system is not well understood. Thu, 15 Jan 2026 12:00:00 GMT https://www.dmmoody.com/notes/overengineering-is-a-signal