engineering
Rate limiting from a single application instance is a solved problem; rate limiting across a fleet of instances with consistent enforcement is harder than it looks. The algorithm choice matters less than the coordination strategy, and the patterns that work treat consistency as a tunable knob r
history
The bicycle as we know it — diamond frame, equal-sized wheels, chain drive, pneumatic tires — converged in roughly 1885, almost seventy years after the first two-wheeled human-powered vehicle. Every recognizable feature had a separate inventor, and most of the dead ends along the way looked sen
engineering
A webhook replay button is one of the highest-trust features a webhook API can offer, and one of the easiest to design wrong. The shape that customers actually want is replay-by-event-ID, not replay-by-time-range, and the discipline that makes it safe is consumer-side idempotency that is docume
engineering
Lock contention shows up as inexplicable slow queries, queries that get faster when traffic decreases, and tail-latency spikes that correlate with nothing in your application logs. The detection is mostly knowing where to look, and the avoidance is mostly knowing what kinds of transactions hold
engineering
INSERT statements are the wrong tool for bulk loads. COPY moves data into Postgres at 10-100x the throughput, but the default invocation will lock the table, blow out the WAL, and starve concurrent queries. The patterns that survive production are about what you do around COPY, not COPY itself.
engineering
A single global rate limit lets one noisy tenant slow down everyone else. A per-tenant rate limit lets one expensive endpoint slow down everything that tenant does. The right design is a small matrix of limits at different scopes, and the wrong design is to keep adding global limits one at a ti
engineering
Most application metrics are the wrong type for the question they are trying to answer. A counter measures totals over time, a gauge measures a current value, and a histogram measures distributions. Picking the wrong one produces metrics that look right and tell you nothing.
history
The pin tumbler lock you use today is a 4000-year-old Egyptian design, refined by Romans, mass-produced by Yale, and now formally equivalent to the cryptographic key-exchange protocols that secure the internet. The continuity is one of the strangest in the history of engineering.
engineering
Most container health checks confuse three different questions into one endpoint, and the result is restarts during initialization, traffic to unready instances, and outages caused by the health check itself. The three-probe pattern fixes this.
engineering
Most API documentation is written for the wrong audience. Customers do not read sequentially. They scan for the four sections that answer their actual questions. The patterns that produce docs developers use and the discipline that keeps them from rotting.
history
The pulley does not invent itself. The chronology from rope-on-a-tree-branch to compound block-and-tackle spans 3000 years, and the most consequential invention in the lineage came in 1853 when a man stood on a platform in New York and cut the rope holding it up.
engineering
The default pool size in most ORMs is wrong for your workload. Little's Law gives you the right answer, the metrics that confirm it, and the failure modes that come from getting it wrong in either direction.