engineering
Database triggers occupy a strange position in the engineering toolkit. They are powerful, well-supported in every major relational database, and capable of expressing constraints that the application layer cannot enforce reliably. They are also one of the most reliable producers of "I have no idea why this row changed&
history
The standard story of computing places the foundational moment somewhere between Charles Babbage's Analytical Engine in the 1830s and Alan Turing's 1936 paper on computable numbers. The standard story is missing thirty years and an industrial machine. The actual moment when a device first separated the
engineering
The first database course teaches normalization as a virtue: every fact stored once, foreign keys instead of duplicated columns, third normal form as the goal. The discipline is well-founded — duplicated data drifts apart, schema changes ripple through copies in inconsistent ways, and disk was once expensive enough that storing the
engineering
Every SaaS company eventually builds internal tools. Customer support needs to look up a user's account state and reset their password. Finance needs to issue manual refunds and adjust subscriptions. Engineering needs to inspect a customer's data when debugging an integration issue. Sales needs to grant
engineering
Stripe Subscriptions look simple in the documentation. You create a customer, attach a payment method, create a subscription with a price ID, and the recurring charges happen automatically. The first month works. The trouble starts when customers change plans, cancel mid-cycle, upgrade in the middle of a billing period, or
engineering
Streaming replication is the default in Postgres and the only kind most teams ever set up. The primary streams the WAL — the binary write-ahead log — to one or more replicas, which apply it block-for-block. The result is a byte-identical replica that lags the primary by network round trip plus apply
history
The schoolroom story of the telephone is straightforward. Alexander Graham Bell, working in Boston as a teacher of the deaf, invented the device in 1876, demonstrated it that summer, and patented an invention that became the foundation of one of the largest industrial empires of the twentieth century. The story
engineering
The first job queue most teams build is a single consumer reading from a SQLite or Postgres table in a tight polling loop. It works fine until it doesn't. The "doesn't" usually arrives suddenly: a slow job clogs the consumer, jobs back up, the
history
The schoolroom story of telecommunications begins with Samuel Morse and the 1844 Washington-to-Baltimore line carrying "What hath God wrought?" The story usually skips fifty years of working continental communication networks that operated by line-of-sight optical signaling, employed thousands of operators across multiple national systems, and worked well enough
engineering
Most API teams configure Cache-Control once when they ship the API and never touch HTTP caching again. The result is one of two failure modes: caches that lie because the freshness window was set without thinking, or caches that do nothing because everything is marked private no-cache. Both modes leave
engineering
Most product teams pass through a phase where they build an internal SDK for their own API. The intentions are good: to encapsulate authentication, to provide typed bindings, to give developers a faster path to a working integration. The execution often goes wrong in predictable ways: the SDK lags the
engineering
The schoolroom story of multi-region SaaS goes through a globally distributed database with strong consistency, automatic failover, and transparent routing. The cost of that story in 2026 is six figures of monthly database spend, ongoing operational tax, and a non-trivial probability that the system is slower than a single-region setup