What six production incidents and one near-miss taught us about proving not only what a notification did, but why it didn't. A failed notification leaves evidence: an error, a retry, a DLQ entry, a provider response. A notification that never entered the system leaves nothing. That was the
Every over-the-air update hides a bootstrapping problem: the software that applies updates is itself software, and can be broken by an update. When a bad image lands on a sensor module inside a pet feeding station — a device with no screen, no buttons, no port anyone will plug into — nobody
Every app with user photos eventually adopts the same two defaults, each picked independently, each obviously correct on its own: sign every media URL fresh per request, so a link can't be shared, guessed, or replayed after it should have expired — and cache fetched images to disk, so
A controlled-impedance PCB is easy to get right once. The difficult part is getting it right again six months later, when the board has a different connector, a new processor, a changed power section, a second PCB supplier, and someone opens the original layout and says, “We can keep the
While working on the SEO setup of a website, I came across a small task related to connecting the website with its social media presence. The website already had social media profiles, but I needed to make sure that the relevant profiles were properly connected as part of the website&
How architecture rules stop being preferences. Someone on the team opens a pull request. One line, added to a service class: @cache def resolve_plan(code: str) -> Plan: ... It gets approved, and of course it does. It's memoization on a lookup that looks pure, it takes
Our pet-health assistant streams its answers token by token. Under load, something odd showed up: response times for completely unrelated endpoints climbed in lockstep with how many people were mid-conversation. History reads, a settings fetch, a suggestion request. CPU sat close to idle. Nothing was throttled, nothing was retrying, no
We removed a cache last week to fix a stale-data bug, and the actual result was discovering that one of our endpoints had been taking two seconds for months. Nobody had filed a ticket about it. Nobody knew. The cache had been quietly absorbing it the entire time, and it
What happened when we made a physical transducer and a call to a language model the same kind of object - one manifest, one reading envelope, one store, and four guards that run at every boot.
A smart bowl reading looks like this: 120 g served, 82 g eaten, 340 seconds, 7:14 a.m. It is perfectly precise and almost meaningless on its own. A vet note is the opposite: rich with meaning ("mild tartar, monitor appetite"), structured not at all. To answer