A practical guide to indexing Postgres under load: how B-tree indexes actually get used, why composite column order matters, covering and partial indexes, reading EXPLAIN, and the write-side cost that makes 'just add an index' the wrong default.
A Go developer's honest account of picking up Clojure — what took real adjustment (parens, dynamic typing, the JVM) and what turned out to be genuinely better (the REPL, immutability by default, and treating every program as data transformation).
How I keep a data-heavy re-frame/Reagent single-page app responsive: layering the subscription signal graph, pushing derefs down so only changed components re-render, and windowing large tables instead of rendering everything.
How to make order and payment endpoints safe to retry: client-supplied idempotency keys, a Postgres-backed store that survives concurrent duplicates, and the trade-offs around scope, TTL, and in-flight requests — in Go.