Notes from our projects, including what we got wrong.

$ cat ./blog/direct-s3-upload-instead-of-through-your-backend.md | head -1

Upload to S3 with a signed URL instead of through your backend▍

from /work/aws-cost-reduction-eight-times

$ cat ./blog/aws-bill-eight-times-too-large.md | head -1

From $24,000 to $2,000 a month on AWS: the three causes I found▍

from /work/aws-cost-reduction-eight-times

$ cat ./blog/zero-downtime-database-migration-with-a-way-back.md | head -1

A rollback in seconds let us migrate PHP to Node during the day▍

from /work/zero-downtime-php-to-node-migration

$ cat ./blog/three-bug-classes-your-tools-cannot-see.md | head -1

Three kinds of design system bug that TypeScript and ESLint miss▍

from /work/cross-platform-design-system

$ cat ./blog/a-real-page-is-a-better-test-than-a-component.md | head -1

Testing a design system on a real page: 7 components and 8 gaps▍

from /work/cross-platform-design-system

$ cat ./blog/the-hand-written-version-was-the-biggest.md | head -1

A half-built design system made our page bigger than plain HTML▍

from /work/cross-platform-design-system

$ cat ./blog/serverless-websockets-you-pay-for-silence.md | head -1

Serverless WebSocket costs: connection minutes rarely dominate▍

from /work/analytics-two-million-writes-per-day

$ cat ./blog/messaging-app-on-aws-and-where-it-stops.md | head -1

Serverless chat on AWS: $19 a month at 100 users, and its limits▍

from /work/analytics-two-million-writes-per-day

$ cat ./blog/the-fool-who-believes-what-he-reads.md | head -1

The biggest fool: six confident AI errors in one afternoon▍

from /blog/serverless-websockets-you-pay-for-silence

$ cat ./blog/we-never-had-a-storage-problem.md | head -1

Self-hosted InfluxDB stayed cheaper because of per-query pricing▍

from /work/analytics-two-million-writes-per-day

$ cat ./blog/influxdb-cardinality-fields-not-tags.md | head -1

InfluxDB cardinality: keep user and device IDs out of tags▍

from /work/analytics-two-million-writes-per-day

$ cat ./blog/split-the-reason-not-the-component.md | head -1

Where I split web and React Native code in our design system▍

from /work/cross-platform-design-system

$ cat ./blog/optimizing-under-a-query-you-dont-control.md | head -1

Speeding up a Redshift report when the query and schema are fixed▍

from /work/query-optimization-under-fixed-schema

$ cat ./blog/immutable-documents-created-vs-valid.md | head -1

Separating when a record is created from when it becomes valid▍

from /work/immutable-issued-documents

$ cat ./blog/neo4j-file-permissions.md | head -1

Why I modeled file permissions in Neo4j instead of SQL tables▍

from /work/permissions-as-a-graph

$ cat ./blog/thermal-printing-a-logo.md | head -1

Printing a logo on a thermal receipt printer from React Native▍

from /work/react-native-hardware-native-modules

$ cat ./blog/same-design-built-twice.md | head -1

Our design system as a skill made an AI agent at least 2× faster▍

from /work/cross-platform-design-system

$ cat ./blog/react-native-nfc-passport-turbo-module.md | head -1

Reading a passport's NFC chip from React Native▍

from /work/react-native-hardware-native-modules

$ cat ./blog/technical-due-diligence-read-the-bill-first.md | head -1

Technical due diligence: read the bill before the code▍

from /work/aws-cost-reduction-eight-times

$ cat ./blog/software-team-in-bosnia-what-to-check.md | head -1

Working with a software team in Bosnia and Herzegovina: what to check▍

from