Dispatches from the work in progress
The hub board inside our feeding station reports air quality, light and motion to the rest of the device over a CAN bus. The firmware queued a frame. The controller accepted it. And nothing — nothing at all — appeared on the wire. There was no error code to chase, no exception,
A notification system that only asks "should this be sent?" will eventually send everything, correctly, all at once and the person holding the phone will switch it off. This post is about the opposite failure, and it's the one users actually complain about: everything arrived, every
Every automated check answers a question about code that exists and paths that run. The defects that survive a mature pipeline live outside both — and they announce themselves the same way a healthy system does.
How clear engineering documentation prevented costly misinterpretation while taking Everbowl from design files to physical hardware. Introduction A CAD model shows what a part looks like. A manufacturing drawing has to communicate what the part actually needs to be. That difference mattered more and more as we moved Everbowl from
What a cross-account DynamoDB migration taught us about the gap between "validated" and "true." A dry-run validates your read path. Only the cutover validates your write path. Everything expensive lives in the gap between the two. We learned this while moving a few hundred DynamoDB tables
"Why is Max scratching more this week?" Somewhere in Max's data, the makings of an answer exist: his bowl logged a food switch on July 5, the new kibble's ingredient list includes chicken meal, his tracker has flagged more nighttime restlessness since July 8,
How working through a simple checklist changed the way I look at web design, development, and testing. While working on a Design-Testing Checklist, I started noticing something I hadn't really thought about before. A web page doesn't become “ready” just because the design is finished. There
The workload, before the database. Every smart bowl and collar in our fleet is a small, relentless firehose. A single device emits roughly twenty distinct event types: camera1 and camera2 frames, thermal and segmented images, audio clips, ocular temperature readings, plus a continuous drizzle of humidity, barometer, imu, proximity, weight,
Every team that generates content with an LLM writes the same defensive code twice. First a prompt that ends in "respond with JSON in this exact shape." Then, a week later, the parser that copes with what actually comes back: a stray code fence, a preamble sentence, a
How asking "What are we actually testing?" made Everbowl prototypes more focused, faster, and more useful. Introduction A prototype is easy to build. A useful one is a lot harder. Working on Everbowl taught us that a prototype's value has nothing to do with how close
Three different sources have something to say about Max's appetite this month. His smart bowl has logged five smaller-than-usual breakfasts. A vet note mentions "monitor appetite." A dog-care book says goldens often eat less in summer heat. Do we know Max's appetite has dropped?
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
