The Fix Was Starting Over With a Smaller Blast Radius
An AI-assisted pricing prototype became reviewable only after its scope was separated from shared purchase logic, with explicit dependency checks and a smaller surface for subsequent changes.
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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A `?prototype=1` Flag and 23 Commits: Prototyping a Redesign in Production Code
A query-string prototype flag can separate an internal presentation path from the default experience, but it does not isolate shared writes, totals, or payment contracts. Those seams need deliberate controls and verification.
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The rate-limiter that banned our power users: 302 to 200 redirects look like an attack
How our own rate-limiter banned a power user because 302-to-200 redirect chains look identical to a flood. A three-layer fix that taught the detector what normal traffic looks like.
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We Almost Built an Entitlement System for a Feature That Was Already a Page
When a group of pages needed tier-aware navigation, an existing per-page tier field avoided a parallel UI catalog. One dynamically added page exposed the ordering bug that declarative setup can hide.
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Don't Trust the Green Deploy: Grep the Live File for Your Ticket Marker
A green deployment signal can confirm that a pipeline completed without proving a specific fix reached the serving artifact. Use a traceable artifact marker or a behavior-level check to verify the change that matters.
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Why schedules broke around March 4, 1973: a getTime() digit-count sort bug
A schedule sorted correctly for years until one getTime() value gained a digit. A number-to-string promotion made the sort lexicographic, with a breaking point in 1973.
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Our AI Agent's Memory Was Per-Folder, So Our Clones Never Learned From Each Other
Claude Code's local memory is keyed to the working directory, so separate clones did not automatically share useful context. Durable project knowledge needed a reviewed, Git-tracked home in the repository.
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Our Fix for a System Freeze Caused Its Own 16-Minute Freeze
Two hard freezes in roughly two hours turned a 7.5 GB always-on box into an unavailable agent runner. The immediate temptation was to call it a memory leak. It was not.
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Why a Comment Cannot Hide a Script Delimiter in a Legacy Include
An include comment in an older web application contained a literal closing delimiter that the template scanner could interpret before the JScript block comment existed. The prototype was rewritten to describe the syntax without reproducing the delimiter.
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The Bundle-Ceiling Model: Separating Subscription and Per-Event Cost
A two-layer event-pricing redesign separated recurring platform access from one-time event capacity, then used membership eligibility to keep the resulting choices legible.
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