engineering
A health check endpoint that returns 200 for everything is a load balancer's favorite and an operator's worst friend. The distinction between liveness, readiness, and dependency health is what makes the difference under real production conditions.
engineering
An SLA is a promise to customers that becomes a constraint on engineering. Getting the promise wrong is expensive in either direction: too generous and you cannot deliver, too conservative and customers do not trust the number.
history
The zipper looks like an obvious invention. The history says otherwise: 80 years from first patent to commercial success, multiple bankrupt companies, and a problem that turned out to be much harder than it appeared.
engineering
EXPLAIN ANALYZE tells you how long each operator took. EXPLAIN ANALYZE BUFFERS tells you why. The buffer accounting separates cache hits from disk reads and turns most performance mysteries into questions about cache fit.
engineering
Some operations take longer than a request-response cycle can hold. A status API has to tell the customer what is happening without keeping the connection open. The three patterns are polling, webhooks, and SSE, and they fit different customer profiles.
history
The sundial dominated timekeeping for 4000 years before the mechanical clock. The achievement was not the gnomon but the mathematics that made the markings correct, and the institutional discipline that kept civic time consistent across generations.
engineering
Postgres tables are heap-organized: rows live wherever there is free space. For most queries this does not matter. For range scans on a correlated column, physical order matters enormously, and CLUSTER is the tool that fixes it.
engineering
Indexes bloat. They corrupt rarely. They become suboptimal when their definition changes. The classic REINDEX takes an ACCESS EXCLUSIVE lock that production cannot tolerate. REINDEX CONCURRENTLY is the answer most teams do not know about.
engineering
Most status pages are green almost always and green during outages. The reasons are operational and political, not technical. Here is what a trustworthy status page actually looks like and how to build one.
engineering
pg_dump is what most teams reach for and what most teams should not rely on alone. The honest backup strategy combines logical dumps for portability with physical base backups plus WAL archiving for point-in-time recovery.
engineering
Rate limit documentation is one of the most consistently underdone surfaces in B2B API design. Customers do not need a treatise; they need three numbers and an example. Most APIs deliver neither.
engineering
BRIN indexes are the rare Postgres feature that can replace a 10GB B-tree with a 1MB index on the same column, with almost no maintenance cost. They are also wrong for most tables. Knowing which case you have is the entire skill.