A New Feature Is the Best Fuzz-Tester for Your Existing Data Model
A new guard exposed a missing lifecycle flag. When a feature needs a real domain fact, adding it to the shared status model can be safer than re-deriving it in one consumer.
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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The most valuable line in an agent's ruleset: verify the fix in the browser before claiming it's fixed
One line in an agent ruleset beats any clever prompt: do not claim a fix until you reload the page and watch the behavior in a real browser.
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GetAccountFilter and the Case for an Explicit Context You Can Override
A helper function in our SaaS app had a default argument that pointed at the wrong account. Fixing it meant threading the same eight-character override through 27 call sites by hand.
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The ambient-global bug: when "current account" is a mutable global 100 call sites read
We shipped a feature that let an admin pick a child event from a dropdown, and the moment they picked one, every save started writing to the wrong account. No error. No exception.
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The ambient-global bug: when current account is a mutable global your whole app reads
A legacy web platform had two globals that were always equal, until a new feature made them diverge. What followed was a 91-line-by-91-line hand audit of a bug class with no stack trace and no grep that tells you what's broken.
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A 47,490-line JavaScript file and what it tells you about a profitable legacy app
Two 'current account' globals were equal until a context switch split them and broke hundreds of call sites in one 47,490-line file.
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Reworking a vector-retrieval scoring formula: stop letting raw similarity be 100% of the base
Fold similarity, importance, heat, and state into a weighted base that sums to 1.0, and save additive bumps for transient urgency. How we rebuilt a retrieval ranker.
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Moving Claude Code Off Your C: Drive: The 12.4 GB VM Bundle and the UWP Permission Wall
Claude Code ate our C: drive. Not a slow creep of logs and caches either. One file: a 12.4 GB claudevm.bundle sitting in AppData, the sandbox VM the desktop build spins up to run tools.
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An Evening of Progressive Disclosure: Four Commits to Hide Everything Behind 'Details'
Four commits in two hours to hide a wall of fields behind one Details seam. Progressive disclosure is a convergence you iterate into, not a one-time call.
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A Client Tree-Walk That Was Really a Server Business Rule
A client-side delete gate re-derived a node count and treated plan price as money received. Moving the decision to server-owned counts and transaction totals aligned the gate with its actual policy.
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