How to Implement PayPal in a Microservice Architecture Using NestJS, gRPC, and Docker
Md Tarikul Islam |
In this tutorial, you'll build a production-ready PayPal payment service using NestJS microservices. Along the way, you'll learn how to isolate payment logic into its own service, communicate between... read more
The Observer Design Pattern Handbook: Event-Driven Architecture & Domain-Driven Design in Dart
Oluwaseyi Fatunmole |
Every application, at some point, has to deal with a fundamental challenge: something happens, and several other things need to react to it. A user logs in, and the app needs to save a token, cache th... read more
A Beginner's Guide to Python: Hands-On Projects to Get You Coding
Beau Carnes |
Have you been wanting to learn how to code but found it a bit too overwhelming or confusing? We just published a brand new course on the freeCodeCamp.org YouTube channel that is designed specifically... read more
Intro to Shaders: JavaScript and p5.js Course for Beginners
Beau Carnes |
Are you ready to unlock the true rendering power of your computer and create breathtaking visuals? We just published a new course on the freeCodeCamp.org YouTube channel that will teach you the fundam... read more
Master Full-Stack Mobile Development with React Native
Beau Carnes |
Do you want to get into mobile development and build cross-platform applications? We just published a comprehensive new course on the freeCodeCamp.org YouTube channel that will teach you how to build... read more
Understanding Dijkstra's Algorithm
Beau Carnes |
In 1956, a young programmer was taking his girlfriend shopping in Amsterdam. Feeling tired, they sat down at a cafe terrace for a cup of coffee. In the 20 minutes it took to finish their drinks, he co... read more
How to Fix Common Web Application Security Vulnerabilities in Node.js
Hackita |
Here's something that tends to surprise developers who are new to security: most web vulnerabilities aren't the result of sophisticated attacks. They come from code patterns that look completely reaso... read more
Why "It Worked on My Machine" Still Happens in 2026
Manish Shivanandhan |
Every engineering team has said it at least once: "It works on my machine." The phrase has become a running joke in software, but it's rarely funny when it happens in production. A feature passes ever... read more
How I Used Harness Engineering to Make Our Company AI-Native
Tech With RJ |
Most companies say they want to "adopt AI". In practice this usually means a chatbot bolted onto a website. Meanwhile, engineers using AI coding tools hit the opposite wall. The AI writes code fast, b... read more
How to Build a RAG Chatbot for Your Docs with Node.js, Google Gemini, and pgvector
Zia Ullah |
I was helping a team that had a 200-page API documentation PDF. Every new engineer spent their first two weeks Ctrl+F-ing through it, asking the same questions in Slack, getting redirected to the same... read more