Hurricane failover for a homelab assistant without paying Bedrock prices
My homelab assistant lives on an LXC in the garage. Hurricane season runs June through November on the Gulf Coast. A two-week power loss takes my whole…
Read →TOPIC 0x4B·AWS
Category
aws
27 posts tagged aws.
Brand-aware location reminders without a custom geocoder
I wanted to add "remind me when I'm at any Walmart" to a location-reminder feature, alongside the existing "remind me when I get home" pin-based…
Read →When every summer storm is a high-severity alert
A safety-monitoring side project I run paged me at 09:00 with "dangerous weather conditions near you. Conditions: Thunderstorm." It was a routine summer…
Read →Moderate risk alert at midnight, awake at the desk
A side-project safety app generated a moderate-severity risk alert for me at 00:28 local time. I was at my desk, awake, trading messages with two…
Read →How to survive AWS toll-free SMS registration
A toll-free SMS number for a personal safety project I run took several denial cycles before AWS approved it. The denials were all about wording in the…
Read →Cutting MX records to SES when your domain loops back to itself
I had cut over the MX records on several personal domains to AWS SES, because I wanted every incoming email going through a Lambda that writes to…
Read →Using AppSync as a pub/sub fan-out without any data source
I had two clients — a web app and a native iOS app — both polling my backend every few seconds to learn that an assistant reply had finished. Polling…
Read →Bref 2 to 3 and provided.al2 to al2023, the gotchas
AWS sent the usual EOL notice for the provided.al2 Lambda runtime. I had 13 functions on Bref 2 / al2 spread across two serverless projects. The…
Read →Disabled the schedule. Got paged anyway.
I disabled a stuck check-in schedule at 09:05. At 09:33 my phone buzzed with "Chester Frazier hasn't responded to their check-in." The schedule was…
Read →Five identical schedules, thirteen SMS in ten minutes
09:33 to 09:43 on a Friday morning: thirteen SMS messages, several push notifications, all from my own safety app, all to me. The trigger was five…
Read →Per-day-of-week sleep windows for a safety app
A safety app I run was firing "missed check-in" pre-alerts at 7am on Saturdays. I don't get up at 7am on Saturdays. The fix was moving from one global…
Read →Auditing 22 references to GSIs that don't exist
A pre-release audit pass on a backend I run turned up 22 places where the code passed IndexName: foo-index to a DynamoDB query on a table where foo-index…
Read →Updating a DynamoDB row by the wrong key shape, for a year
A pre-release endpoint sweep on a backend I run turned up two 500s on the check-in respond and snooze endpoints. The cause was old: a composite-key table…
Read →PHP loose comparison turned an empty endpoint into a 500
A backend I run was returning 500s on GET /api.php with no endpoint= query param. Should obviously be a 400. Tracking it down landed me on one of those…
Read →Replacing a binary threshold cliff with a one-hour ramp
The inactivity-monitor cron on a side-project safety app was paging me at 7:01 AM, every morning, with "you haven't checked in." I was asleep. The cause…
Read →A risk email every fifteen minutes about nothing
The risk-monitor cron on a side project I run was emailing me every 15 minutes with "risk factor appeared" or "risk factor resolved" for low-severity…
Read →Why the sleep-window learner kept collapsing to the wrong four hours
The v1 sleep-window learner for a side-project safety app produced a sleep window of 01:00–05:00 for me. My actual sleep is more like 23:00–07:00. The…
Read →94% SpO2 is not an emergency
I got a high-severity SMS from my own safety app: "may be at risk. Factors: Low blood oxygen: 94%." 94% is normal. Consumer pulse oximeters have a ±2%…
Read →Heartbeats were polluting my activity table
The phone in a side-project safety app posts a stationary_heartbeat every few minutes when it's not moving — so the server knows the device is alive even…
Read →Sixty-five lines ahead of git, in production
I went to deploy a fix to a backend Lambda and stopped halfway through because the file I was about to overwrite was 65 lines ahead of the repo…
Read →Dynamo as inbox, with a passkey
I built a single-page mail reader on top of the DynamoDB table my mail pipeline writes to. Three-pane layout (inbox list / messages / body), search…
Read →Personal mail as a serverless pipeline (and a forwarder identity trap)
I wanted every email to my personal domains stored in DynamoDB as the primary read surface, with Google Workspace continuing to receive a copy as a cold…
Read →Sensor Offline alerts while traveling, twice
A safety app I run pinged me every hour with "Sensor Offline — no data from IFTTT in the last 24 hours" while I was on a trip. That sensor is the motion…
Read →Plaid to DynamoDB with read-time categorization
I wanted a personal-finance dashboard that I owned end-to-end. Plaid on one end, DynamoDB on the other, one Lambda in between, and categorization rules…
Read →A personal location heatmap on cheap Lambda infrastructure
I had years of GPS pings in a database from a side project. I wanted to look at where I'd actually been on a map — heatmap of every ping, markers for the…
Read →One Lambda serving a résumé and a blog, routed by Host header
I had a static résumé at one subdomain and wanted a blog at another. Two Lambdas felt absurd for what is functionally two HTML generators. So I put both…
Read →An inventory app for a family craft business
A family member runs a craft-supply brand and needed a product inventory catalog. I built one weekend project: a public catalog page, an admin page, and…
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