freeCodeCamp

Codex vs Claude Code: Which AI Coding Assistant to Choose

Manish Shivanandhan |
AI coding assistants have evolved from simple autocomplete tools into capable development agents that can write code, debug applications, refactor projects, and even execute complex workflows. Among t... read more

Product Experimentation: Stop Early Without P-Hacking Using mSPRT and Sequential Testing in Python

Rudrendu Paul |
Your AI product experiment reaches statistical significance on day 14 of a planned 30-day run, measuring a causal inference question: did the LLM-based feature genuinely improve outcomes? Every produc... read more

Mastering JavaScript Dates and Times

Beau Carnes |
Managing dates and times in JavaScript is notoriously tricky, often leading to subtle bugs that only surface once an application hits production. To help you master this fundamental skill, the freeCod... read more

How to Defend Your JavaScript App Against Unsafe Data with TypeScript Guard Utilities

Kelechi Apugo |
Picture this: you hit an API endpoint, and you get an API response back. You pass the data straight into your application, and everything looks fine in development. Your mock data is clean, your types... read more

The Cloud Pentesting Problem: Why Traditional Security Models Stop Working at Scale

Manish Shivanandhan |
Cloud adoption changed how companies build software. It changed deployment speed, infrastructure management, and the way engineering teams operate. It also changed the security landscape. Applications... read more

How to Build a Browser-Based PDF Margin Tool Using JavaScript

Bhavin Sheth |
Adding margins to a PDF is a common task when preparing documents for printing, binding, archiving, or sharing professionally. While many PDF editors include this feature, they often require installin... read more

What is a JSON Schema?

Chidiadi Anyanwu |
If you're a developer, you likely work with JSON a lot. But how do you define and validate JSON and prevent problems from malformed JSON data? This article explores what a JSON schema is, some example... read more

How to Build a Zero-Cost Personal Project with PHP, Wasmer, and Cloudflare

Jakub T. Jankiewicz |
Recently, I wanted to reinvigorate my open-source project Clarity, an icon theme for Linux (GTK+). The icons allow users to create custom colors by adding SVG templates. And I wanted to have a platfor... read more

How to Build a Text Compare Tool with HTML, CSS, and JavaScript

Bansidhar Kadiya |
Have you ever tried to spot the differences between two long paragraphs of text? Reading line-by-line to find a missing word or a new sentence is a massive headache. In this tutorial, you'll build you... read more

My Team's Experience Moving from AWS to a PaaS

Manish Shivanandhan |
Most product teams assume infrastructure ownership is simply part of building software. We did too. It wasn’t until we measured how much engineering time was disappearing into operational work that we... read more