Tutorials

Cache-Control and ETag are the two headers that decide whether the browser reuses a response or asks for it again. This guide explains each directive with real code, a diagram of the cache hierarchy, and the mistakes that most often break production.

Database sharding splits a giant table into independent fragments that live on separate servers. This guide explains hash, range, and directory-based strategies, with examples in PostgreSQL and application code.

A Service Worker is a script the browser runs in the background, separate from the page, that can intercept every network request. Thanks to it, a web app can keep working offline, show cached content instantly, and even receive push notifications. This guide explains its full lifecycle and the caching strategies PWAs use in production.

HNSW is the layered graph algorithm that finds the closest vector among millions of embeddings in milliseconds. This article explains how it works internally, shows how to implement it in Python, and compares it with alternatives like IVF and brute-force search.

Canary deployment and blue-green deployment solve the same problem (avoiding downtime when deploying new code) in different ways. This guide explains how each works, when to choose one over the other, and how to set up your first canary with Argo Rollouts.

The count-min sketch is a probabilistic data structure that estimates how many times an event occurred without storing each individual instance. Using a small matrix and several hash functions, systems like Redis and Apache Flink count frequencies in massive streams with just a few kilobytes of memory.

The actor model is a concurrency paradigm where each actor processes messages in isolation, without shared memory. Erlang popularized it in telecommunications, and today it powers Akka, Elixir/OTP, and Microsoft Orleans. This guide explains how it works, when to use it, and how to write your first supervised actor.

OpenTelemetry connects traces, metrics, and logs under an open standard, without locking you into a monitoring vendor. It includes step-by-step instrumentation in Node.js and a comparison of the most popular backends for storing traces.