4 essays on Systems.
A deliberately over-built essay that puts every rendering feature the blog supports on one page — headings, math, a live diagram, an interactive 3D plot, code chrome, margin notes and figures — so nothing can hide.
Once retrieval works, the next wall is latency — and most of the latency you can actually control turns out to be a question of scheduling, not hardware.
An index tells you where things are. It does not tell you what they mean — and confusing the two is where retrieval quietly starts to lie.
The cheapest retrieval system that could possibly work, and what it taught me before I reached for anything heavier.