Notes on design, engineering, and growth.
Practical writing on building and scaling software products — how we think, and how we work.
July 3, 20264 min read
My tests passed. The client redrew everything by hand.
The duct-routing engine shipped with a green test suite. The client's response was to print the output and redraw every run by hand — which turned out to be the real specification, delivered late.
EngineeringTesting
Read article →
June 29, 20264 min read
The most important part of an AI assistant is what it refuses to do
Everyone is racing to let AI handle more. In a real business — money, contracts, regulated processes — the value is in what you forbid it to do. Notes on building an AI layer you can actually trust.
AIAutomation
Read article →
June 28, 20264 min read
Most HVAC software still sizes ducts wrong. Here's what right looks like.
A 5-inch duct for 110 CFM isn't a typo — it's what velocity-only sizing produces. Why rule-of-thumb duct sizing keeps failing, and what proper ACCA Manual J and Manual D actually take.
HVACDuct design
Read article →