The Duplicated-Derivation Bug: One Fragile Expression in Four Queries
Four queries each derived the same entity key inline and disagreed. Why duplicated derivation is a live correctness bug, and the one-resolver fix.
The build log
Notes from running agents in production.
Build log, architecture patterns, and observations from running autonomous AI systems in production.
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Writing an AI_CONTEXT.md So Your Assistant Stops Rediscovering Your Codebase
A committed AI context file turns repeated codebase explanations and product guardrails into a reviewable project artifact that sessions can be instructed to read first.
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Trading Badge Soup for One Human Sentence
We deleted four metadata badges from a list row and replaced them with one state-aware sentence like 'Waiting on you'. A list view serves one decision per row.
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A Tiptap Editor That's Invisible Until You Add ProseMirror's Base CSS
A headless Tiptap editor mounted successfully but offered no visible empty state. A minimum height, deliberate wrapper styling, and the placeholder extension made the editing surface discoverable.
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Tiptap v3 Fires onFocus During Init, So Subscribe to the DOM Instead
A formatting toolbar opened when a Tiptap editor initialized instead of when a person interacted with it. Moving the listener to the editor DOM node avoided the unwanted initial state in this integration.
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Shipping a Whole Analytics Suite Into a Legacy Admin
Five report pages inside a legacy admin application, one page pattern, and the habit that paid: check in your review SQL as the canonical business definition.
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Six Production Releases in One Day: Anatomy of a Hotfix Train
A minor release and five hotfixes shipped across one day on a long-running legacy web application. Keeping each hotfix small made rollback scope easier to reason about under pressure.
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'Newest First' Is a Re-Priority Problem, Not an ORDER BY
A new folder needed to appear first without undoing the order people had arranged by hand. The fix moved to the create path, and it left a wrinkle behind.
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PayPal Pay-Later Messages Won't Re-Render, So Destroy the Node and Recreate It
A checkout total updated after a coupon, but its Pay Later message retained the old amount. Replacing the SDK-owned DOM node and scheduling a fresh render resolved the stale estimate.
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Same SHAs in Two Repos: Why Commit-Count Metrics Lie in a Clone Workflow
A commit-count script treated mirrors and local clones as separate work, turning 23 unique commits into an inflated total of 134. The fix was to aggregate unique commit IDs, not repository directories.
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