Courses

Over time, knowledge has been passed down in various forms. Before writing was invented in ancient Mesopotamia (modern-day Iraq), laws, history, myths, songs, and other information were all transferred from generation to generation orally.…

I recently worked on a project where a Node.js application used Vite to compile its frontend. It worked in a browser-hosted development environment, but its image build failed after the move to Azure Container Registry. The build reported …

Most application search setups force a trade-off: settle for simple text filters, or manage a separate search cluster like Elasticsearch with complex synchronization pipelines. In a new video course on the freeCodeCamp.org YouTube channel,…

Your smart ring or watch has many useful jobs, including learning your usual physiological patterns and showing you when they change. Resting heart rate, heart rate variability (HRV), temperature, and breathing rate can all contribute to t…

A straight line equation is a good place to start understanding how a neural network works. It's what we explored in my previous article, How Neural Networks Work – Explained Using the Straight Line Equation (y=ax+b). But, what if the rela…

I got tired of coding agents telling me the frontend work was done when nobody had opened the frontend. You've probably seen the routine. The agent changes some code, runs the formatter, the type checker, and the tests, everything comes ba…

Many AI agent tutorials start with a language model, give it a few tools, and run a loop until it produces an answer. That's enough to demonstrate tool calling, but it leaves the interesting engineering questions unanswered. What happens w…

Most Android tutorials stop at "it runs on the emulator." But getting an app from a blank project to a listing that real people can install from Google Play involves a second half that's rarely discussed in one place: release builds, signi…

A website user interface (UI) used to take hours of writing HTML, CSS, and component code by hand. Now you can describe a page in plain words and let an AI coding tool write the first version. But the result depends on your prompt. A short…

In my previous article, I explored operational conformance: how to evaluate whether observed evidence satisfies an operational specification. That gives us a useful point-in-time question: Does the system satisfy the specification right no…

A good final answer doesn't prove that an agentic AI workflow was correct. This book develops a code-backed method for verifying execution and business outcomes from authoritative state and using that evidence to gate releases. You'll find…

This guided lab walks you through migrating a small payments app, with a React UI and Express API running on a single AWS EC2 instance, while PostgreSQL stays on AWS. You’ll move the UI and API to Google Kubernetes Engine without changing …

System design is one of the most important skills for software engineers today. Whether you're applying for senior or staff-level positions or just looking to level up your architectural knowledge, understanding how to design systems at sc…

Artificial intelligence models like GPT-4 and Claude require massive, highly complex physical infrastructure. We just published a new full-length course on the freeCodeCamp.org YouTube channel that takes you deep inside the data centers po…

Every team that ships software eventually builds a staging environment. And every team that builds a staging environment eventually discovers the same problem. Staging is shared. One environment, many pull requests. Someone deploys a half-…