Tutorials

GraphQL is a query language that lets the client request exactly the data it needs, without over-fetching or chaining multiple calls. This guide explains how it works internally, with code examples and an honest comparison with REST.

A JWT token lets a server confirm who you are without querying the database again on every request. This guide explains its structure, how to sign it with Node.js, and its real security risks.

Regex engines aren’t magic: they parse the pattern, build an automaton, and run it against the text. This article explains how they work internally, why some are vulnerable to ReDoS, and when it makes sense to switch to an automaton-based engine like RE2.

Skip lists are a probabilistic data structure that Redis uses to implement sorted sets and that LevelDB uses in its MemTable. Instead of balancing a tree with rotations, each node flips a coin to decide how many levels of shortcuts to have. The result is expected O(log n) performance with an implementation much simpler than an AVL or red-black tree.

LSM trees are the data structure that lets RocksDB, Cassandra, and LevelDB handle intensive writes without rewriting existing files. This article explains memtable, WAL, SSTables, and compaction with real code examples and commands.

WebRTC connects two browsers in real time without relying on a central server to transmit video, audio, or files. STUN, TURN, and ICE solve the NAT traversal problem and let you code your first peer-to-peer connection in just a few lines.

Python is now one of the most widely used languages in the world and the standard in artificial intelligence and data science. What it is, what it’s good for, its history, and how to take your first steps with version 3.14.

The Raft algorithm solves how a distributed cluster elects a single leader and replicates its log without corrupting data during node failures. Etcd, Kubernetes, Consul, and CockroachDB use it in production to maintain strong consistency.