Tag

system design

4 articles

Exactly-once semantics on at-least-once infrastructure

Exactly-once delivery is impossible at the transport layer. The pattern that gives you the semantics anyway: at-least-once delivery plus an idempotent writer.

How to detect benchmark contamination in LLMs

A model scores 92% on MMLU — but did it learn the concepts or memorize the answers? Four detection strategies, from first principles.

LLM-as-a-judge: how to evaluate AI without fooling yourself

LLM-as-a-judge from first principles — when to use it, how to design rubrics, the three biases that skew scores, and when to use something simpler.

How columnar storage actually works (and why ClickHouse is fast)

Why ClickHouse queries billions of rows in milliseconds — columnar storage, compression, and the MergeTree engine explained from first principles.