Master Modern React Routing: TanStack Router Crash Course
Beau Carnes |
Routing in modern web applications has evolved far beyond simply rendering a component based on a URL path. Developers today want end-to-end type safety, automated code splitting, seamless URL search... read more
How to Create System Design Diagrams using Python
Zaira Hira |
Creating system architecture design diagrams is an important part of technical documentation. As system complexity grows, clarity within teams becomes even more important. But creating diagrams from s... read more
Build and Train a 25M Parameter LLM From Scratch on Your CPU
Beau Carnes |
You don't need a massive GPU cluster to learn how modern frontier AI works. In our new video on the freeCodeCamp.org YouTube channel, you will build, pre-train, and fine-tune a working 25-million para... read more
What Claude Code Can and Can't Do with Full Access Inside a Docker Sandbox
Chirag Agrawal |
Claude Code can do more than suggest a fix. It can edit files, install dependencies, run tests, and start your application. But letting it finish a task on its own raises a practical question: how muc... read more
How to Encrypt PII in Data Pipelines While Keeping It Searchable
Lakshmi Mahabaleshwara |
At Intuit, my team built a data pipeline that processed TurboTax e-filing data. This data needed to be made available for dashboards, analytics, and other downstream use cases. One of the biggest chal... read more
API Authentication & Authorization: An Engineering Deep Dive into Mechanisms, Trade-offs, and Failure Modes
Oluwaseyi Fatunmole |
Every API has some form of authentication. But having authentication and getting it right are two completely different things. I've reviewed production systems where JWTs had no expiry. Systems where... read more
How to Break the AI Coding Agent Fix Loop
Amir Gabay |
You've likely seen this movie before: something breaks in an app you built with an AI coding agent. You ask the agent to fix it. It "fixes" it. But the bug is still there, or a second bug appears. So... read more
How to Use NestJS Observe: An Observability Handbook for Devs
Pacifique Linjanja |
Observability isn't a new problem, and NestJS is certainly not the first ecosystem to tackle it. But NestJS Observe is interesting because it asks a more specific question: what happens when observabi... read more
How AI Is Changing Email Deliverability: A Technical Guide to Sender Reputation and Inbox Placement
Reetain Raina |
Sending an email doesn't always mean it will reach the recipient's inbox. Sometimes, an email is sent successfully by an application but ends up in the spam folder instead. This can be a real problem... read more
The Engineering Anatomy of API Vulnerabilities: A Deep Dive into the OWASP API Security Top 10
Oluwaseyi Fatunmole |
Most security articles read like threat reports. They describe vulnerabilities from the outside looking in: what an attacker does, what the impact is, and how many systems are affected globally. That'... read more