Best of freeCodeCamp — October 2025

1. 1
   Article

   freeCodeCamp·27w

   How to Improve Your Programming Skills by Building Games

   Building games teaches essential programming skills that extend beyond game development. Through creating games, developers learn systems thinking, event-driven architecture, performance optimization, and debugging complex states. Games force practical application of math concepts like vectors and trigonometry, while teaching component-based architecture similar to modern frameworks. The hands-on experience with user input handling, reusable code patterns, and creative problem-solving translates directly to building better web applications, backend services, and software systems. Even simple 2D games provide valuable lessons in modular design, UX instincts, and managing code complexity that traditional tutorials rarely offer.

   288

   19
2. 2
   Article

   freeCodeCamp·28w

   Master Technical Interviews by Learning Data Structures and Algorithms

   A comprehensive 49-hour course covering data structures and algorithms for technical interview preparation. The course teaches fundamental concepts including time and space complexity analysis with Big O notation, and covers major data structures (arrays, linked lists, stacks, queues, trees, graphs) and algorithm patterns (sliding window, two pointers, dynamic programming, backtracking, greedy algorithms). Created by Parth Vyas and available on freeCodeCamp's YouTube channel.

   137

   5
3. 3
   Article

   freeCodeCamp·27w

   How to Overcome a Negative Performance Review and Become a Better Developer

   A software engineer shares their experience being placed on a Performance Improvement Plan at Google after underperforming for a year. Despite working 60-hour weeks and becoming a code owner for a gaming feature, they didn't complete the project within the two-month deadline and were let go. The experience taught them discipline, focus, and ownership that transformed their approach to engineering and career development. They now apply the same structured methodology to their job search, targeting smaller companies using open-source technologies.

   78
4. 4
   Article

   freeCodeCamp·31w

   Build a Full Stack Movie Streaming App with Go, React, MongoDB, OpenAI

   A comprehensive 15-hour course teaches building MagicStream, a production-ready movie streaming application with AI-powered recommendations. The stack includes Go with Gin-Gonic for the backend API, React for the frontend, MongoDB for data storage, and OpenAI integration via LangChainGo for intelligent movie suggestions. The course covers secure authentication with http-only cookies, token validation middleware, and deployment to Atlas, Render, and Vercel.

   74
5. 5
   Article

   freeCodeCamp·30w

   Learn How to Use Pointers in Go – With Example Code

   A comprehensive guide to understanding and using pointers in Go, covering memory fundamentals, pointer declaration and dereferencing, common pitfalls like nil pointers, and practical applications including pointer receivers for struct methods. The guide explains how pointers enable efficient memory usage by avoiding unnecessary copies, allow shared state mutation, and are essential for method receivers. It also introduces weak pointers in Go 1.24+ for advanced memory management scenarios like caching, and includes practical exercises with solutions.

   45

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6. 6
   Article

   freeCodeCamp·30w

   How to Containerize and Deploy Your Node.js Applications

   Learn how to containerize a Node.js application using Docker and deploy it to the cloud. The guide covers writing a Dockerfile, building and testing container images locally, pushing images to Docker Hub, and deploying to a cloud platform. It explains how containers solve environment inconsistencies, make applications portable, and simplify scaling and updates in production environments.

   44
7. 7
   Article

   freeCodeCamp·30w

   How to Use the Compound Components Pattern in React: Prop Soup to Flexible UIs

   Learn how to implement the Compound Components Pattern in React to build flexible, reusable UI components. The tutorial demonstrates refactoring a rigid modal component into a composable design using parent-child component relationships with shared state. Through hands-on examples building modal and accordion components, you'll understand how this pattern eliminates prop drilling, improves maintainability, and enables LEGO-like composition of UI elements without sacrificing flexibility.

   30

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8. 8
   Article

   freeCodeCamp·28w

   The React Handbook for Beginners – JSX, Hooks, and Rendering Explained

   Comprehensive guide covering React fundamentals including JSX syntax, component creation, event handling, state management with hooks, and rendering concepts. Explains how to add React to HTML pages, work with JSX expressions, handle lists with keys, manage component state with useState, and understand the difference between refs, state, and variables. Includes practical examples and best practices for building user interfaces.

   28
9. 9
   Article

   freeCodeCamp·27w

   How to Use Closures in Go

   Closures in Go are functions that capture and retain access to variables from their surrounding scope, even after the outer function has finished executing. The guide covers how Go's escape analysis moves captured variables to the heap, common pitfalls like the loop variable trap where all closures reference the same variable, and practical patterns including memoization, event handlers, and concurrent pipelines. It explains how to create closures through various methods, handle them safely in goroutines using channels or mutexes, and addresses memory implications of heap-allocated captured variables.

   27
10. 10
    Article

    freeCodeCamp·30w

    Docker Build Tutorial: Learn Contexts, Architecture, and Performance Optimization Techniques

    Docker build is the process of creating container images from Dockerfiles and build contexts. The architecture uses two components: Buildx (client interface) and BuildKit (build engine) that communicate through on-demand file transfers for efficiency. Build contexts can be local directories, Git repositories, or remote tarballs. Common mistakes include wrong context directories, including massive unnecessary files, and inefficient layer caching. Optimization techniques include using .dockerignore files, multi-stage builds, specific base images, proper layer ordering for cache reuse, and combining RUN commands. The guide covers troubleshooting build issues, measuring performance metrics, and implementing security best practices with build secrets.

    27

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11. 11
    Article

    freeCodeCamp·27w

    How to Build a CRUD App with TanStack Start and TanStackDB (with RxDB Integration)

    Learn to build a full-stack CRUD todo application using TanStack Start, TanStackDB, and RxDB for local-first data persistence. The guide covers setting up a reactive database client with IndexedDB storage, creating collections with schemas, implementing CRUD operations, and building a React frontend. It also compares TanStack Start with Next.js and Remix, highlighting its modular architecture, Vite-powered performance, and deep TypeScript integration for developers seeking flexibility without framework conventions.

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12. 12
    Article

    freeCodeCamp·28w

    How to Build a Full-Stack Serverless CRUD App using AWS and React

    A comprehensive guide to building a serverless coffee shop management system using AWS services. Covers setting up DynamoDB for data storage, creating Lambda functions with reusable layers, exposing APIs through API Gateway, implementing authentication with Cognito, and deploying a React frontend via S3 and CloudFront. Includes detailed steps for configuring IAM roles, handling CORS, creating CRUD operations, and troubleshooting common deployment issues.

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13. 13
    Article

    freeCodeCamp·27w

    Mobile App Development with Dart and Flutter

    A comprehensive tutorial covering Dart fundamentals and Flutter mobile app development through 20 step-by-step programs. The course includes interactive code playbacks with an AI tutor, covering widgets, state management, navigation, and data storage. Designed for developers with basic programming knowledge in any language who want to build cross-platform mobile applications.

    17

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14. 14
    Article

    freeCodeCamp·28w

    How to Turn Websites into LLM-Ready Data Using Firecrawl

    Firecrawl is an open-source API tool that converts websites into clean, structured data formats like Markdown, HTML, and JSON for use with large language models. The guide covers scraping single pages, crawling entire websites, and extracting structured data using AI-powered features. It demonstrates both the paid API approach with a free tier and self-hosting options using platforms like Sevalla. The tool handles JavaScript-heavy sites, manages proxies and anti-bot systems automatically, and can extract specific information using natural language prompts or JSON schemas.

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    Article

    freeCodeCamp·27w

    Serverless and Microservices with C# & Azure

    A comprehensive 2-hour video course covering serverless architecture and microservices development using C# and Azure. The course progresses from fundamental concepts to production-ready implementations, including Azure Functions, Docker containers, Kubernetes orchestration, and .NET Aspire. Topics include serverless architecture patterns, microservices design patterns, onion architecture, Azure triggers, background functions, IoT functions, and practical route planning microservices.

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    Article

    freeCodeCamp·30w

    How to Build a Custom AI Chat Application with Next.js: Fine-Tune GPT Using Your Data

    Learn to fine-tune GPT-4.1 models with custom data and build a production-ready chat application using Next.js 15. The guide covers scraping and preparing training datasets in JSONL format, submitting data to OpenAI for supervised fine-tuning, and creating a modern chat interface with real-time streaming responses using the Vercel AI SDK and shadcn/ui components. Includes complete code examples for data preparation scripts, API route integration, and frontend implementation with proper error handling and UX considerations.

    10
17. 17
    Article

    freeCodeCamp·31w

    Machine Learning vs Deep Learning vs Generative AI - What are the Differences?

    An introductory guide explaining the relationships and differences between machine learning, deep learning, and generative AI. Covers fundamental concepts like supervised and unsupervised learning, how neural networks process data through layers, and real-world applications ranging from spam detection to ChatGPT. Includes a comparison table showing data requirements, computational costs, and appropriate use cases for each technology.

    10