Knowledge

Engineering 2 articles How applications behave at runtime, how to find where time really goes, and how to measure before optimising. Web Development 3 articles Practical explanations of the web's building blocks — HTTP requests, encoding, data formats — with the mistakes people actually make. Security 2 articles Authentication across services, browser security headers, and what each protection does and does not cover. Privacy 1 article What keeping data in the browser protects, what it doesn't, and how to judge a tool before pasting data into it. Education Technology 2 articles Design decisions behind online exams, question banks and lessons — from the work on Smart Edu. Tools Guides 1 article Background for the utilities on Zerethon Tools: what the formats and identifiers are, and when to use which.

Engineering Finding the Real Bottleneck in a Laravel Request Why guessing at slow requests wastes time, how a runtime trace splits a request into measurable steps, and how to read the result to decide what to optimise. Read article → Engineering Runtime Analysis vs Static Analysis: What Each Can Tell You Static analysis reads code; runtime analysis watches it run. What each one is good at, the blind spots of both, and how to combine them. Read article → Web Development How a Request Flows Through a Laravel Application From public/index.php to the response: the HTTP kernel, middleware, routing, controllers, the service container and the database — and where time is usually spent. Read article → Web Development URL Encoding Explained: encodeURI vs encodeURIComponent Why URLs need percent-encoding, which characters are reserved, the difference between encoding a whole URL and a single parameter, and the "+" vs "%20" trap. Read article → Web Development JSON Syntax Errors: The Common Ones and How to Fix Them Trailing commas, single quotes, comments, unquoted keys, NaN and big numbers — why JSON rejects them, how to read the parser's error, and when JSON5 is the better fit. Read article → Tools Guides UUID v4 vs UUID v7: Which Should You Use? How random v4 and time-ordered v7 UUIDs are built, why v7 is friendlier to database indexes, what each leaks, and how to choose. Read article → Privacy Browser-Based Encryption: What It Can and Cannot Protect How in-browser AES-256-GCM with PBKDF2 works, what "client-side" really guarantees, and the threats it does not cover — illustrated with the Zerethon Tools AES tool. Read article → Security Single Sign-On Across Subdomains: How One Login Works for Many Products A practical guide to giving several web products one login with OAuth 2.0 and OpenID Connect — a central identity provider, PKCE, short-lived signed tokens — and the trade-offs to plan for. Read article → Security HTTP Security Headers Explained: CSP, HSTS, Framing and nosniff What each common security header defends against, sensible starting values, how to roll out a Content Security Policy without breaking a site, and how to check what you actually send. Read article → Education Technology Designing Fair Online Exams: Shuffling, Timers, Checkpoints and Integrity The design decisions behind Smart Edu's exam engine — per-attempt papers, server-side time limits, autosave checkpoints, signed submissions and answer-reveal policies — and their limits. Read article → Education Technology Organising a Question Bank Teachers Can Actually Use Lessons from building Smart Edu's question bank: importing from Word and Excel with a review step, flagging duplicates without blocking, grouping by topic, and keeping AI-generated questions behind human review. Read article →