If you've built a Django API and you're wondering how to add authentication so that each user can only access their own data, you're in the right place. Most Django tutorials teach you session-based a

If your team is preparing for a SOC 2 Type II review, this handbook is for you. It's a self-contained guide to the exact 90-day timeline, 14 critical controls, and evidence collection infrastructure t

JavaScript is famously single-threaded, yet it powers highly complex, interactive web applications without freezing up. How is this possible? The answer lies in the Event Loop. The Event Loop is a cor

In our daily life, we use the word "average" all the time: average salary, average marks, average age, and so on. Let's take the case of a retail shop. If we're looking at the average order value to u

New products are dropping daily, and smart sellers are quietly stacking profits. If you understand how SEO landing pages actually work today, you’re not guessing. Instead, you're building assets that

If you're coming to DynamoDB from a relational background, the first thing to understand is this: it's a completely different way of thinking. DynamoDB isn't a relational database, it's a NoSQL key-va

A few months ago, I was reviewing a pull request that added three new API endpoints. The diff was clean. Tests passed. The agent that generated it had even written sensible authorisation checks. By ev

Most frontend engineers don't choose microservices. They inherit them. One day you're fetching data from a single API, and the next you're stitching together responses from five services, each with it

PDF files are everywhere. From invoices and reports to résumés and documents, they’re one of the most common file formats we deal with. But there’s a common problem: PDFs can get large quickly. If you

Today Quincy Larson interviews Rachel An Fernandez. She's a computer science student at Stanford and the youngest instructor at the entire university. She recently helped organize TreeHacks, Stanford'

Every product experimentation team running causal inference on LLM-based features eventually hits the same wall: when users click "Try our AI assistant," the volunteers aren't a random sample. Your pr

Building a single AI agent that answers questions or runs searches is a solved problem. A handful of tutorials and a few hours of work will get you there. What most tutorials skip is the engineering l

You've completed three AWS courses. You have notes from a dozen Docker tutorials. You know what Kubernetes is, what CI/CD means, and you can explain Infrastructure as Code without hesitating. And yet

In today's digital world, spam is no longer just an annoyance - it's a growing security threat. To combat this, developers often turn to machine learning to build intelligent filters that can distingu

Imagine that you want to share your source code with someone who doesn’t have Go installed on their computer. Unfortunately, this person won’t be able to run your application. Even if they do have Go

Ready to dive into IT but don’t know where to start? freeCodeCamp just dropped the Ultimate IT Fundamentals Bootcamp For Absolute Beginners course. This is a a brand new, full-length course created by

Are you ready to be inspired by the next generation of tech innovators? freeCodeCamp.org just dropped a new documentary on our YouTube channel that dives deep into Stanford’s TreeHacks 2026, one of th

Are you ready to be inspired by the next generation of tech innovators? freeCodeCamp.org just dropped a new documentary on our YouTube channel that dives deep into Stanford’s TreeHacks 2026, one of th

Most sites think they're getting AI citations because their brand shows up in ChatGPT answers, but they're not. Visibility and citation are different numbers, and the gap between them is where the lea

I typically build my projects using Next.js 14 (App Router) and Supabase for authentication along with Postgres. The default deployment choice for a Next.js app is usually Vercel, and for good reason:

Have you ever wondered how platforms like Webflow, Notion, or Hashnode serve thousands of users from a single codebase — each with their own unique URL? The answer is multi-tenancy: an architecture wh

Can you achieve a massive milestone while you're still in high school other than just getting high grades? You may be thinking: school alone is plenty of work! And it often is. But if you set your min

Most developers live in their terminal. You run commands, debug pipelines, manage infrastructure, and navigate codebases, all from a shell prompt. But despite how central the terminal is to developer

If you've ever wanted to add an interface to a codebase and gotten pushback, you already know the argument: "That's twice the code for the same thing." And honestly? It was a fair point. You'd write t

Secure software requires both design-time and code-time protection. STRIDE threat modeling helps identify risks early in system design, while SonarQube enforces secure coding practices through static

If you've been storing AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY as GitHub Secrets to deploy to AWS, you're not alone. It's the most common approach and it's also one of the biggest security risks i

Working with PDFs is part of everyday development. Sometimes you don’t need the entire document. You just need a few pages — maybe a specific section, a report summary, or selected invoice pages. Most

What if you could build your own LLM, one that speaks your native language, all from scratch? That's exactly what we'll do in this tutorial. The best way to understand how LLMs work is by actually bui

Every RAG system I've seen — including the one I wrote a handbook about on this site — has the same fundamental problem. It doesn't learn. You ingest 500 documents. You ask a question. The system retr

When you run a single AI agent, debugging is straightforward. You read the log, you see what happened. When you run five agents in a swarm, each spawning its own tool calls and producing its own outpu

Most end-to-end test suites drive a real browser and click through an app like a user. They check whether a page renders and whether elements appear. But they don't check whether the numbers on those

This tutorial is a complete, real-world guide to building a production-ready CI/CD pipeline using Jenkins, Docker Compose, and Traefik on a single Linux server. You’ll learn how to expose services on

Most engineering teams don't set out to manage infrastructure. They start with a product idea, a customer need, or a business problem. Infrastructure enters the picture as a means to an end. Servers n

Modern production systems generate more data than most developers can realistically process. Every request emits logs. Every service exports metrics. Every dependency introduces another layer of signa

Most teams don't struggle because they can't fix problems. They struggle because they fix the wrong thing. An API fails in production. You restart the service, errors go away, and it feels resolved. U

Your team shipped an LLM-based summaries feature to wave 1 workspaces at week 20 and now the post-launch doc is due. You need a causal effect number, a specific estimate you can defend to a statistici

Every time you spin up GPU infrastructure, you do the same thing: install CUDA drivers, DCGM, apply OS‑level GPU tuning, and fight dependency issues. Same old ritual every single time, wasting expensi

Take your creative web development to the next level by building an interactive 3D cozy cafe portfolio from scratch using Blender and Three.js. We just posted a course on the freeCodeCamp YouTube chan

While many guides explain how to set up Continuous Integration pipelines, not very many show you how to debug them when things go wrong across multiple layers. This is a common experience when contrib

Working with PDFs is something almost every developer needs to know how to do. Sometimes you need to combine reports or invoices, or simply merge multiple documents into a single clean file. Most tool

You've set up Stripe. Checkout works. Customers can pay. But what happens after payment? The webhook handler is where most payment integrations silently break. Your server crashes halfway through gran

When someone searches for information today, they increasingly turn to AI models like ChatGPT, Perplexity, or Gemini instead of Google. But these models don't return a list of links. They synthesize a

As our lives become increasingly digital, the need for secure networking solutions is more important than ever. Whether you’re browsing the web or managing a corporate network, the role of proxies is

Each GPU generation pushes against the same constraint: memory. Models grow faster than memory capacity, forcing engineers into complex multi-GPU setups, aggressive quantization, or painful trade-offs

"Just use Postgres" has been circulating as advice for years, but most articles arguing for it are opinion pieces. I wanted hard numbers. So I built a benchmark suite that pits vanilla PostgreSQL agai

If you're a software developer today, it's almost impossible to avoid the noise of AI( Artificial Intelligence) and its impact on the industry. You open X or LinkedIn in the morning, and the majority

Do you ever spend a lot of time doing small repetitive tasks like copying data from an email into a spreadsheet or manually moving files between folders. We just posted a new course on the freeCodeCam

Backend applications are required to send emails to users to deliver notifications and maintain communication outside the application interface. These emails usually contain information specific to ea

Self‑taught developers often begin with the same “starter pack”: a laptop, internet access, and sheer determination. What they lack, however, is structured guidance, a defined curriculum, or any form

This tutorial shows you how to run WordPress as a headless CMS with an Astro frontend deployed to Cloudflare Pages. For a project I was recently working on, the requirement was to use WordPress as the

If you have a Github profile, you might overlook the many ways you can customize it – and that's completely understandable. After all, at its core, GitHub is a home for your code. But beyond repositor

Large language models can write code quickly, but they still misremember APIs, miss version-specific details, and forget what they learned at the end of a session. That is the problem Context Hub is t

Chrome OS runs on a read-only filesystem. You can't install executables on the host. There's no traditional desktop environment. Everything that interacts with the underlying system does so through a

Microservices architecture enables healthcare portals to scale, secure sensitive data, and evolve rapidly. Using ASP.NET 10 and C#, you can build independent REST APIs for services like patients, appo

Today Quincy Larson interviews Jessica Rose. She's a dev and teacher who's worked on open data projects at Mozilla and lots of open source projects. We talk about: How the whole world is hard, and ho

A quiet shift is happening inside modern companies. It's not visible in dashboards. It's not tracked in logs. It's not approved by IT or security teams. Yet it's everywhere. Employees are using AI too

Enormous amounts of data are constantly generated on the open web. Product prices change, job listings go live and get taken down, news articles are published, and company information gets updated. Fo

Every developer eventually runs into a slow query. The table has grown from a few hundred rows to a few million, and what used to take milliseconds now takes seconds — or worse. The fix, more often th

They say data is the new gold. But navigating through a large dataset to meet the demands of consumers in record time still gives backend devs a headache. Conventional database queries often aren't to

Creating a data platform has been made easier by cloud data analytics platforms like Databricks, Snowflake, and BigQuery. They offer excellent ramp-up and scaling options for small to mid-size teams.

OpenAI Codex is a specialized artificial intelligence system designed to translate natural language into code. We just published a course on the freeCodeCamp.org YouTube channel that will teach you ho

Level up your system design skills! We just published a course on the freeCodeCamp.org YouTube channel that progresses from foundational concepts to production-ready systems, covering databases, scali

Generating PDF files is something most developers eventually need to do. Whether it’s invoices, reports, or downloadable documents, PDFs are still one of the most widely used formats. The usual approa

Infrastructure has undergone a fundamental shift over the past decade. What was once configured manually through dashboards and shell access is now defined declaratively in code. This shift isn't just

The communication layer is one of the few architectural decisions that touches everything in your apps. It determines your latency floor, how independently teams can deploy, how failures propagate, an

Large JavaScript bundles can slow down your application. When too much code loads at once, users wait longer for the first paint and pages feel less responsive. Search engines may also rank slower sit

In August 2012, Knight Capital, a major trading firm in the United States, deployed faulty trading software to its production system. The system used this incorrect configuration data and it triggered

In 2026, the concept of “location” on the internet has evolved from a broad regional signal into a hyper-specific, neighbourhood-level determinant of what users see. Search engines, advertising platfo

I used to spend too long deciding what to wear, even when my closet was full. That frustration made the problem feel very clear to me: it was not about having fewer clothes. It was about having better

Admin dashboards are one of the most common real-world UI components you will build as a React developer. At the heart of nearly every dashboard is a sidebar, a persistent navigation panel that organi

In February 2024, a Canadian tribunal ruled that Air Canada was liable for its chatbot's fabricated bereavement policy. The airline argued the chatbot was "a separate legal entity," but the tribunal d

The first time I tried to follow a DevOps tutorial, it told me to sign up for AWS. I did. I spun up an EC2 instance, followed along for an hour, and then forgot to shut it down. A week later I had a $

There's a moment in every Flutter developer's journey where the inheritance model starts to crack. You have a StatefulWidget for a screen that plays animations. You write the animation logic carefully

Over the years I've participated in dozens of technical interviews. I've answered technical questions one-on-one with the CTO and in a group with the dev team. I've taken quizzes with a timer and buil

On March 27, 2026, Zhipu AI quietly pushed an update to their open-weight model line. GLM-5.1, they claim, now performs at 94.6% of Claude Opus 4.6 on coding benchmarks. That's a 28% improvement over

Svelte is a front-end framework for building fast and interactive web applications. Unlike many other well-known frameworks, it doesn’t use a virtual DOM. Instead, it turns your code into efficient Ja

Six months ago, Stack Overflow processed 108,563 questions in a single month. By December 2025, that number had fallen to 3,862. A 78% collapse in two years. The explanation everyone reaches for is th

Every data pipeline makes a fundamental choice before any code is written: does it process data in chunks on a schedule, or does it process data continuously as it arrives? This choice — batch versus

If you've bought a laptop in the last few years, there's a good chance it's running an ARM processor. Apple's M-series chips put ARM on the map for developers, but the real revolution is happening ins

When you work with GitHub Pull Requests, you're basically asking someone else to review your code and merge it into the main project. In small projects, this is manageable. In larger open-source proje

Commitment of Traders (COT) data gets referenced a lot in commodity trading, especially when people talk about crowded positioning, speculative sentiment, or reversal risk. But most of that discussion

Today Quincy Larson interviews Mark Mahoney. He worked as a dev before becoming a computer science professor. He's taught computer science for 23 years at Carthage College, a 180-year-old US universit

Learn CUDA programming for NVIDIA Hopper GPUs. We just posted a course on the freeCodeCamp.org YouTube channel that will teach you to build efficient WGMMA pipelines and leverage Cutlass optimizations

We've all been there: You open ChatGPT, drop a prompt. "Extract all emails from this sheet and categorize by sentiment." It gives you something close. You correct it, it apologizes, and gives you a ne

Have you ever wondered how platforms like Etsy, Uber, or Teachable handle payments for thousands of sellers? The answer is a multi-vendor marketplace: an application where merchants can sign up, list

Most AI agent tutorials make the same mistake: they route every task to the most expensive model available. A character count doesn't need GPT-4. A presence check doesn't need Sonnet. A regex doesn't

If you've ever tried to process video in the browser, like for a video editing or streaming app, your options were either to process video on a server (expensive) or to use ffmpeg.js (clunky). With th

Since the early 2000s, Bluetooth has been the dominant way we listen to wireless audio, powering everything from the first mono headsets to today's true wireless earbuds. But the underlying technology

OpenClaw is getting attention because it turns a popular AI idea into something you can actually run yourself. Instead of opening one more browser tab, you run a Gateway on your own machine or server

Have you ever watched a flock of starlings at sunset? Thousands of birds, wheeling and swooping in perfect unison. There's no leader, no choreographer, no bird with a clipboard shouting directions. Ju

We just posted a comprehensive course on the freeCodeCamp YouTube channel focused on AI drone programming using Python. Created by Murtaza, this tutorial utilizes the Pyimverse simulator, a high-fidel

Artificial intelligence (AI) has seen remarkable advancements over the years, with AI models growing in size and complexity. Among the innovative approaches gaining traction today is the Mixture of Ex

Building modern React applications requires more than just functionality. It also demands responsive layouts and accessible user experiences. By combining semantic HTML, responsive design techniques,

Imagine this scenario: you ship a feature in the morning. By afternoon, users are rage-clicking a button and your UI starts showing nonsense: out-of-order results, missing updates, and random failures

AI assistants are powerful. They can answer questions, summarize documents, and write code. But out of the box they can't check your phone bill, file an insurance rebuttal, or track your deadlines acr

As a developer, there's nothing worse than finding out from an angry user that your website is down. Usually, you don't know your server crashed until someone complains. And while many SaaS tools can

Kubernetes doesn't know who you are. It has no user database, no built-in login system, no password file. When you run kubectl get pods, Kubernetes receives an HTTP request and asks one question: who

Most machine learning deployments don’t fail because the model is bad. They fail because of packaging. Teams often spend months fine-tuning models (adjusting hyperparameters and improving architecture

A “market pulse” screen is basically the tab you keep open when you don’t want to stare at charts all day. It tells you what’s moving right now, what’s unusually volatile, and which names are starting

There's a moment that most Flutter developers experience at some point in their careers. You're building a screen that needs a user's name, their latest five posts, and the like count on each post. Se

Every Next.js project starts the same way: you run npx create-next-app, write a few pages, maybe add an API route or two, and things feel clean. Then the project grows. Features multiply. A second app

If you've learned some Python basics but still feel stuck when it comes to building something real, you're not alone. Many beginners go through tutorials, learn about variables, functions, and loops,

If you’ve ever worked on something like an inventory system, billing dashboard, or even a small internal tool, chances are you’ve needed to generate barcodes at some point. Most developers either rely

Today Quincy Larson interviews Chris Griffing is a software engineer and prolific streamer of live coding on Twitch. He spent 10 years as a "snowboard bum" doing odd jobs at ski resorts to facilitate

For many software engineers and SaaS founders, writing code is the easy part. But the marketing and sales grind feels like an uphill battle. If you’d rather be building features than chasing leads you

Most full-stack React tutorials stop at "Hello World." They show you how to render a component, maybe fetch some data, and call it a day. But when you sit down to build a real SaaS application, you im

Hi everyone! We (Jess, Carmen, and Eda) are excited to announce the next installation of our free and online bootcamp. We support learners as they work their way through the freeCodeCamp Responsive We

Using AI tools is an important part of being a software developer. We just posted a course on the freeCodeCamp.org YouTube channel that will teach you how to use AI tools to become more productive as

Using AI tools is an important part of being a software developer. We just posted a course on the freeCodeCamp.org YouTube channel that will teach you how to use AI tools to become more productive as

There's a particular kind of frustration that every mobile developer has felt at some point. You're building a Flutter application, and you want to add an AI feature. Perhaps it's something that reads

Cloud infrastructure has become deeply programmable over the past decade. Nearly every platform exposes APIs that allow developers to create applications, provision databases, configure networking, an

Every digital marketing agency has someone whose job involves opening a spreadsheet, visiting each client URL, checking the title tag, meta description, and H1, noting broken links, and pasting everyt

When you're building Flutter applications that have multiple tabs or screens, one of the most common challenges you'll face is maintaining state across navigation without breaking the user experience.

Modern web applications increasingly need to evolve faster than a single team can maintain a monolithic codebase. Product teams often want to add features independently, experiment with new capabiliti

QR codes are everywhere today. You scan them to open websites, make payments, connect to WiFi, or even download apps. Most developers use online tools when they need one quickly. But just like image c

Tab components are everywhere: dashboards, settings panels, product pages. But most implementations are static, lifeless, and forgettable. What if your tabs felt alive, with smooth spring animations,

APIs power everything from mobile apps to enterprise platforms, quietly handling millions of requests per day. Without safeguards, a single misconfigured client or a burst of automated traffic can ove

Every developer eventually has a workflow they repeat. A way they write commit messages. A checklist they run before opening a pull request. A structure they follow when reviewing code. They do it man

Next.js App Router splits your app into Server Components and Client Components. Server Components run on the server and keep secrets safe. Client Components run in the browser and handle interactivit

In Kubernetes, when you need to isolate workloads, you might start by using namespaces. Namespaces provide a simple way to separate workloads within a single cluster. But as your requirements grow, es

If you've ever needed your database to automatically respond to changes – like logging every update to a sensitive table, enforcing a business rule before an insert, or syncing derived data after a de

GitHub Copilot costs $10/month, and I'd been using it for two years without thinking twice. But when Claude Code launched, I got curious. What if I just... switched? I didn't want to just add Claude C

Cloud-native development enables enterprise .NET applications to scale and remain resilient in the cloud. Using Azure DevOps CI/CD pipelines, you can automate building, testing, and deploying applicat

Checkboxes are a fundamental part of modern UI design. They allow users to make multiple selections, confirm actions, and control features with ease. And while they may appear simple, designing intera

Today Quincy Larson interviews Landon Gray. He's a software engineer who worked at agencies for years. Then he taught himself AI assisted software development. And now he's helping other devs do the s

Have you ever faced a situation as a frontend developer where you needed to show a demo to your product manager, and something was broken in the API response? Or, a production bug where you were block

The Web Speech API is a web browser API that enables web applications to use sound as data in their operations. With the API, web apps can transcribe the speech in sound input and also synthesise spee

The healthcare industry is undergoing a profound transformation powered by artificial intelligence (AI) and data science. No longer limited to administrative automation or basic chat tools, AI now pla

AI literacy isn’t just for developers anymore. It’s a fundamental skill for navigating the modern world. We just posted a course on the freeCodeCamp YouTube channel that will help anyone learn how the

Cluade Code can supercharge your software development. We just posted a full course on the freeCodeCamp.org YouTube channel that will teach you how to use Claude Code to build real-world agentic codin

If someone asked you how secrets flow from AWS Secrets Manager into a running pod, could you explain it confidently? Storing them is straightforward. But handling rotation, stale env vars, and the gap

If you've ever modified a variable inside a Python function and been surprised or confused by what happened to it outside the function, you're not alone. This tripped me up for a long time. Coming fro

SQL (Structured Query Language) is the standard language for managing and manipulating data in relational databases. It's an essential tool that allows you to communicate with the databases that power

When you're working with .NET, interacting with databases (particularly SQL databases) is inevitable. Common approaches involve using ORM (Object Relational Mapping) with tools like Entity Framework.

These days, businesses and startups rely on well-designed databases to manage vast amounts of data. In domains like Healthcare, E-commerce, and Fintech/Banking, a solid database design ensures data in

"I have never enjoyed coding as much as I do today — because I no longer have to deal with the minutia." — Boris Cherny, Head of Claude Code, Anthropic This handbook is a complete, professional intro

Hi! I'm Daria, and I'm a software engineering student with a keen interest in data visualization. I've been actively exploring various visualization tools through small pet projects, and I'd like to s

Hugging Face has become the "operating system" of the modern AI revolution. We just posted a comprehensive new course on the freeCodeCamp.org YouTube channel that will teach you about Hugging Face and

Google Maps has been the default choice for developers building location-based applications for years. But for many teams, especially those operating at scale, pricing has become a real concern. Googl

The Hidden Bugs in How Most Developers Store Money Imagine you're building the backend for a million-dollar fintech app. You store each user's balance as a single number in the database. It feels simp

Ask an AI coding agent to build a feature and it will probably do a decent job. Ask it to review its own work and it will tell you everything looks great. This is the fundamental problem with single-p

In 2018, RedLock's cloud security research team discovered that Tesla's Kubernetes dashboard was exposed to the public internet with no password on it. An attacker had found it, deployed pods inside T

LLMs are great at writing market commentary. The problem is they can sound confident even when they haven't looked at any data. That’s fine for casual chat, but it’s not fine if you’re building a feat

If you've spent any time shipping Flutter apps manually, you already know the drill. Someone on the team finishes a feature, builds the APK locally, signs it (hopefully with the right keystore), uploa

I spent 64% of my weekly Claude budget before Wednesday building a tool designed to reduce Claude usage. That's the kind of irony that deserves its own specification. The tool is spec-writer: a Claude

Have you ever used an undo button in an app or scheduled tasks to run later? Both of these rely on the same idea: turning actions into objects. That's the command pattern. Instead of calling a method

Training machine learning models usually starts out being organized and ends up in absolute chaos. We’ve all been there: dozens of experiments scattered across random notebooks, and model files saved

We just published a massive new course on the freeCodeCamp.org YouTube channel that will change the way you think about programming. Instead of just chatting with an AI, you can now learn how to use C

Modern software development moves fast. Teams deploy code many times a day. New environments appear and disappear constantly. In this world, manual infrastructure setup simply doesn't scale. For years

Maybe this sounds familiar: your production container crashes at 3 AM. By the time you wake up, it's been throwing the same error for 2 hours. You SSH in, pull logs, decode the cryptic stack trace, Go

Image conversion is one of those small tasks developers run into occasionally. You might need to convert a PNG to JPEG to reduce size, or export an image to WebP for better performance. Most developer

Today Quincy Larson interviews Chris Coyier. He's a front-end developer and co-founder of CodePen and the CSS Tricks blog. He has also recorded more than 700 podcasts about software engineering. We ta

JWT auth feels clean until a stolen token still looks valid to your server. That's the real problem: a bearer token proves possession of a token, but it doesn't prove possession of a trusted device. I

Testing is the unsung hero of software development because shipping features is only half the battle. We just published a comprehensive course on the freeCodeCamp.org YouTube channel that will teach y

Forms are often the gatekeepers to conversions on a site or application. Abandoned carts, partially signed-up users, and users who stop engaging with your app are often thanks to friction with forms.

Hello, friends! My name is Ramazan, and I'm a front-end developer and enthusiast who loves looking at familiar things in web development from new perspectives. You might have heard of functional progr

The hard part of building a presentation is figuring out the story. What are you trying to say? What’s the structure? Which sections build on which? Where does the data go, table or bullets? Before th

Setting up Ghost CMS (Content Management System) on your local machine is a great way to develop themes and test new features. But if you're using Windows or Docker, you might run into errors that sto

In event-driven systems, two things need to happen when you process a request: you need to save data to your database, and you need to publish an event to a message broker so other services know somet

Most RAG tutorials show you a working demo and call it done. You copy the code, it runs locally, and then you try to put it in production and everything falls apart. This tutorial is different. I run

Mobile application development has evolved over the years. The processes, structure, and syntax we use has changed, as well as the quality and flexibility of the apps we build. One of the major improv

Every developer has been there. You push a one-line fix, grab your coffee, and wait. And wait. Twelve minutes later, your Docker image finishes rebuilding from scratch because something about the cach

Improve your web development skills by building 19 different projects. We just posted a course on the freeCodeCamp.org YouTube channel that will teach you to use HTML, CSS, and JavaScript to make all

Paystack is a seamless payment gateway for businesses to accept online transactions. It is like Stripe but with a focus on Africa. We just posted a course on the freeCodeCamp.org YouTube channel that

Machine learning projects don’t end at training a model in a Jupyter notebook. The hard part is the “last mile”: turning that notebook model into something you can run reliably, update safely, and tru

If you’re still running kubectl apply from your local terminal, you aren’t managing a cluster, you’re babysitting one. I’ve spent more nights than I care to admit staring at a terminal, trying to figu

ngrok is a tunneling tool that lets developers expose a local server to the public internet through a secure URL. In practice, this means you can run a web app on your laptop and instantly make it acc

Computers will, 100% of the time, without fail, do exactly what you tell them to do. It's getting them to do what you want them to do that's the real trick. The gap between what you tell the computer

Building a web application that works only on your local machine is one thing. Building one that is secure, connected to a real database, and accessible to anyone on the internet is another challenge

As a researcher and developer, I found myself spending hours manually searching academic databases, reading abstracts, and trying to synthesize findings across multiple sources. For my work on circula

In 2026, cybersecurity teams face more threats than ever before. Attack surfaces are broad, technology stacks are complex, and adversaries are quick to exploit weak points. Against this backdrop, comp

A few days ago, I ran an experiment with an AI-powered testing agent that lets you write test cases in plain English instead of code. I opened its natural language interface and typed four simple sent

OpenClaw is a self-hosted AI assistant designed to run under your control instead of inside a hosted SaaS platform. It can connect to messaging interfaces, local tools, and model providers while keepi

Most LLM applications look great in a high-fidelity demo. Then they hit the hands of real users and start failing in very predictable yet damaging ways. They answer questions they should not, they bre

This article shows how to build end-to-end, code-first LLM observability in a FastAPI application using the OpenTelemetry Python SDK. Instead of relying on vendor-specific agents or opaque SDKs, we wi

Today Quincy Larson interviews Luke Ciciliano. He's a front-end developer who runs Modern Website Design, a software consultancy that builds solutions for small to medium sized businesses. He taught h

Last year, our ML team shipped a fraud detection model that worked perfectly in a Jupyter notebook. Precision was excellent. Recall numbers looked great. Everyone was excited – until we tried to deplo

Before I started building auth into my own projects, I didn't think too deeply about what was happening to passwords behind the scenes. Like most developers, I installed a library, called a hash funct

Depending on cloud apps means that you don't truly own your notes. If your internet goes down or if the company changes its rules, you could lose access. In this article, you'll learn how to build you

Recursion is when a function solves a problem by calling itself. It sounds odd at first — why would a function call itself? — but once it clicks, you'll find it's often the most natural way to express

In the world of Software Engineering, there are plenty of programming languages to learn. And there are both low-level and high-level options. I’ve tried my hand at a few of them, and the one language

When you create an article, such as a blog post for freeCodeCamp, Hashnode, Medium, or DEV.to, you can help guide the reader by creating a Table of Contents (ToC). In this article, I'll explain how to

Real-time data powers much of modern software: live stock prices, chat applications, sports scores, collaborative tools. And to build these systems, you'll need to understand how real-time communicati

Software development has always evolved alongside the tools we build. There was a time when developers wrote everything in assembly language. Then higher-level languages arrived and made it possible t

Have you ever opened a food delivery app and chosen between "fastest route", "cheapest option", or "fewest stops"? Or picked a payment method at checkout like credit card, PayPal, or wallet balance? B

In any analysis project, raw tables of numbers often don’t tell the full story. Visualisations simplify complexity by transforming data into shapes that our brains can quickly understand, emphasising

I tried out Open Claw two weeks ago. I loved the potential, but did not enjoy the tool itself. I, like many others, struggled with the installation process. And working from Linux, the Mac specific or

Most RAG tutorials end the same way: you've got a working prototype and a bill for a vector database that runs whether anyone's querying it or not. Add an always-on embedding service, a hosted LLM end

Automation is no longer just a "nice-to-have" skill, it powers modern software development. To help you master automation and CI/CD, we’ve just released a massive 17-hour Jenkins course on the freeCod

Hey there! If you're building modern web interfaces, chances are you've already fallen in love with Tailwind CSS for its speed and flexibility. One of the most powerful tools in Tailwind's arsenal is

The goal isn't just to train a model; it's to build a system that understands your specific data as well as you do. We just posted a massive, 12-hour course on the freeCodeCamp.org YouTube channel des

Ever wondered how Gmail knows that an email promising you $10 million is spam? Or how it catches those "You've won a free iPhone!" messages before they reach your inbox? In this tutorial, you'll build

Finding the top K items in a dataset pops up everywhere: from highlighting the hottest posts in a social feed, to detecting the largest transactions in a financial system, or spotting the heaviest use

Every MCP tutorial I've found so far has followed the same basic script: build a server, point Claude Desktop at it, screenshot the chat window, done. This is fine if you want a demo. But it's not fin

Real-time updates are everywhere – like live sports scores, stock tickers, chat applications, and IoT dashboards. If you want to build systems that push data to users the moment it changes, you need t

In this tutorial, you'll build a production-ready voice agent architecture: a browser client that streams audio over WebRTC (Web Real-Time Communication), a backend that mints short-lived session toke

Centering elements in CSS often seems straightforward at first, but it quickly becomes confusing once you start building real layouts. A property like text-align: center; works perfectly for text, yet

I have noticed that many engineers who run Kubernetes in production have never actually watched it heal itself. They know it does. They have read the docs. But they have never seen a ReplicaSet contro

There's a perception problem with Docker Compose. Ask a room full of platform engineers what they think of it, and you'll hear some version of: "It's great for local dev, but we use Kubernetes for rea

Today Quincy Larson interviews Justin Searls. He's a software engineer who cofounded a software agency 15 years ago that's still going – even after he figured out how to make a lot of money quickly an

Vibe coding is about momentum. You open your editor, prompt an AI, stitch pieces together, and suddenly you have something that works. Maybe it’s messy. Maybe the architecture is not perfect. But it’s

Whenever engineers are building AI-powered applications, use of sensitive data is always a top priority. You don't want to send users' data to an external API that you don't control. For me, this happ

As the industry standard for managing the machine learning life cycle, MLflow provides the necessary architecture to build systems that are both reproducible and scalable. We just posted a course on t

The NCA-AIIO certification is an entry-level credential that validates the foundational concepts of AI computing related to infrastructure and operations. We just posted a course on the freeCodeCamp.o

The Model Context Protocol (MCP) is changing how AI applications connect to external tools and data. While some tutorials stop at "connect to GitHub" or "read a file," the real power of MCP is unlocki

Hi everyone. In this handbook, you will learn about the growing world of open source, and how it can shape your career as a developer. Open source is something I found confusing and scary when I first

For years, I thought Open Source Software (OSS) just wasn’t for me. I had no plans to join any OSS communities on top of my existing developer community obligations. Curious about the hype I saw on Bl

In the long history of technological innovation, only a few developments have been as impactful as Large Language Models (LLMs). LLMs are advanced AI systems trained on vast datasets to understand, ge

We just posted a course on the freeCodeCamp.org YouTube channel that will teach you how to build a professional screen recording platform from scratch. Using Next.js 15 and Mux, you will create a "Loo

Most teams are confident they can recover from a major outages until they actually have to. Backups exist, architectures are redundant and a recovery plan is documented somewhere, yet real incidents o

As a computer science instructor, I have long wished that there was a better way to guide others through my code. When I was first learning to program, I was a big fan of traditional programming books

Imagine this situation: A user logs in successfully to your application, but upon loading their dashboard, they see someone else’s data. Why does this happen? The authentication worked, the session is

Today Quincy Larson interviews Carl Brown, who runs the Internet of Bugs YouTube channel and has worked as a dev at Amazon, IBM, Sun Microsystems, and startups for over 37 years. We talk about: The h

The future of software is code that reasons. We just posted a new course on the freeCodeCamp.org YouTube channel designed to take you from Python fundamentals to AI Agent development. This course is a

Stop memorizing isolated commands and start building like a platform engineer. We just posted comprehensive Kubernetes course on the freeCodeCamp.org YouTube channel. This hands-on course is designed

Getting a web developer job today is hard. In 2021, I got my first developer job by sending one direct email and then doing a single live call. That was enough. Later the same year, I found my second

In fintech or wealthtech products, people constantly need quick market context. They need to know why a particular stock moved, what changed recently, or what they should watch next. This usually beco

A REST API documentation is a guide that explains how clients can make use of the REST APIs in an application. It details the available endpoints, how to send requests and what responses to expect. It

Most RAG tutorials end the same way: you've got a working prototype and a bill for a vector database that runs whether anyone's querying it or not. Add an always-on embedding service, a hosted LLM end

Building great software isn't about perfect prompts, it's about a disciplined process. In this guide, I'll share my workflow for shipping secure code: defining clear goals, mapping edge cases, and bui

Stop treating Notion like a digital notebook and start using it as a high-level operating system. We just posted a massive Notion course on the freeCodeCamp.org YouTube channel. This course takes you

In fintech or wealthtech products, people constantly need quick market context. They need to know why a particular stock moved, what changed recently, or what they should watch next. This usually beco

You wake up and open your laptop. Your browser has 27 tabs open, your inbox is overflowing with unread newsletters, and meeting notes are scattered across three apps. Sound familiar? Now imagine you h

How many times have you rewritten the same systems across different Unity projects? Or copied entire folders from an old project, only to spend hours fixing references, renaming namespaces, and adapti

I was recently moved to the marketing team at my company, and that shift has made me reflect more deeply on the role documentation plays in our go-to-market strategy. Before this move, we've had sever

Java is the most widely used programming language for enterprise software, Android development, and university computer science courses. Apple doesn't include Java with macOS, so you need to install i

If you've ever wanted to combine the power of Rust with the interactive goodness of Jupyter notebooks, you're in the right place. Maybe you're tired of compiling every single time you want to test a s

WhatsApp bots are widely used for customer support, automated replies, notifications, and internal tools. Instead of relying on expensive third-party platforms, you can build and deploy your own self-

Today Quincy Larson interviews Shawn Wang. He's a software engineer, founder of the AI Engineer conference, and host of the Latent Space podcast focused on applying the latest models toward getting wo

AI agents are all the rage these days. They’re like traditional chatbots, but they have the ability to utilize a plethora of tools in the background. They can also decide which tool to use and when to use it to answer your questions. In this tutorial...

Your team needs to solve a problem, and there's no clear solution path. Multiple approaches might work, but you're not sure which. Success isn't guaranteed. This is Research, not Development. And if you manage it like Development, things aren't going...

Foreign data wrappers (FDWs) make remote Postgres tables feel local. That convenience is exactly why FDW performance surprises are so common. A query that looks like a normal join can execute like a distributed system: rows move across the network, r...

How does the Internet really work? For many technical jobs it is important to understand computer networking. We just posted a massive 12-hour course that will give you a deep dive into computer networking. Here are the sections covered in this compr...

If you’re a developer working with containers, chances are Docker is your go-to tool. But did you know that there's a whole ecosystem of container runtimes out there? Some are lighter, some are more secure, and some are specifically built for Kuberne...

Have you ever wondered how YouTube notifies you when your favorite channel uploads a new video? Or how your email client alerts you when new messages arrive? These are perfect examples of the observer pattern in action. The observer pattern is a desi...

Performance problems in APIs rarely start as performance problems. They usually start as small design decisions that worked perfectly when the application had ten users, ten records, or a single developer testing locally. Over time, as traffic increa...

Embeddings have transformed how we search text, images, and code. Instead of matching keywords, you compare vectors, which are numerical representations that capture meaning. Similar items end up close together, making it easy to find matches. The sa...

Machine learning tasks usually start in a Python notebook, and for good reason. Notebooks make it easy to explore data, test ideas, and iterate quickly with minimal setup. They give teams a familiar place to experiment while questions remain open and...

This article explains how to design and implement your own circuit breaker in Spring Boot using explicit failure tracking, a scheduler-driven recovery model, and clear state transitions. Instead of relying solely on Resilience4j, we’ll walk through t...

A chess game is usually divided into three phases: the opening, middlegame, and endgame. In the opening phase, each player develops and sets up their pieces. In the middlegame, they plan attacks, execute different tactics and strategies to gain an ad...

If you've ever wondered how chat applications like Slack, Discord, or WhatsApp work behind the scenes, this tutorial will show you. You'll build a real-time chat server from scratch using Go, learning the fundamental concepts that power modern commun...

Today Quincy Larson interviews Robby Russell. Robby created the open-source project Oh My ZSH. Oh My Zsh is a framework for managing your Zsh configuration for your command line terminal. It's been extremely popular among developers for more than a d...

In most languages, the stack and heap are two ways a program stores data in memory, managed by the language runtime. Each is optimized for different use cases, such as fast access or flexible lifetimes. Go follows the same model, but you usually don’...

Extracting text from PDFs sounds simple until you try to do it. And it can be even more challenging for JavaScript developers, with various libraries to choose from and so on. I encountered this problem while I was building my SaaS app. I scoured thr...

Most React developers don’t break the data fetching process all at once. It usually degrades gradually, slowly. Traditionally, you may have used a useEffect here, a loading flag there, and an error state along with it to tackle data fetching. Moving ...

Learn to take a full-stack React, Go, and MongoDB application from local development to a fully containerized production environment. We just posted a full course on the freeCodeCamp.org YouTube channel that will help you master Docker orchestration,...

Nowadays, being able to present an idea, project, or achievement is a must-have skill. The ability to showcase and talk about your work can determine whether you’re getting that degree, funding, or approval. But while effective communication is impor...

For more than a decade, Heroku defined what “developer-friendly deployment” meant. Push code, forget servers, and focus on shipping features. That promise shaped an entire generation of platform-as-a-service products. In 2026, that landscape is chang...

Why Personalization Breaks Most AI Agents Personalization is one of the most requested features in AI-powered applications. Users expect an agent to remember their preferences, adapt to their style, and improve over time. In practice, personalization...

To protect your applications against threats, it’s helpful to understand the methods that attackers can use against you. We just posted a course on the freeCodeCamp.org YouTube channel that will help you master the fundamentals of cybersecurity and e...

Testing is one of those things that every developer knows they should do, but many put off until problems start appearing in production. If you’re building React applications with Vite, there's a testing framework that fits so naturally into your wor...

We just posted a course on the freeCodeCamp.org YouTube channel to help prepare you for the Certified Kubernetes Administrator Certification. This course is designed to provide a deep, practical understanding of Kubernetes administration, from founda...

Design patterns are proven solutions to common problems in software development. If you've ever found yourself writing repetitive object creation code or struggling to manage different types of objects, the factory pattern might be exactly what you n...

Writing code can be similar to writing tutorials. In both cases, you’ll typically need to create and work on multiple drafts before reaching the final version. In an ideal setting, you would write code for a feature, add that code to the staging area...

Hiring the right candidate starts with one time-consuming task: screening résumés. If you’ve ever posted a job opening, you know the pain of hundreds of applications in your inbox, leaving you to spend hours reviewing each résumé manually. In this ar...

A step-by-step guide to containerising a FastAPI application with Docker and deploying it to the cloud for consistent, production-ready delivery. Modern applications rarely live in isolation. They move between laptops, staging servers, and production...

In the world of big data, performance isn't just about bigger clusters – it's about smarter code. Spark is deceptively simple to write but notoriously difficult to optimize, because what you write isn't what Spark executes. Between your transformatio...