freeCodeCamp.org

We're a community of millions of people who are building new skills and getting new jobs together. A 501(c)(3) public charity. Tweets by @abbeyrenn.

[freeCodeCamp.org @freeCodeCamp]

After a Series A, your AWS bill can start climbing fast, and it usually isn't random.

In this guide, Ayobami breaks down 8 common costs that show up after product-market fit.

You'll learn where to look in Cost Explorer and how to cut waste from NAT gateways, logs, staging, data transfer, orphaned resources, and more.

https://t.co/EcyHJxBqLM

[freeCodeCamp.org @freeCodeCamp]

Bluetooth Low Energy powers earbuds, smartwatches, sensors, and many other connected devices.

In this handbook, Nikheel teaches you how to build Bluetooth apps with Zephyr OS from the ground up.

You'll learn about GAP, GATT, services, advertising, custom BLE peripherals, sensor nodes, security, and lots more.

https://t.co/BNjvTMj1u5

[freeCodeCamp.org @freeCodeCamp]

If you're a Flutter dev, you already know Dart. And Dart can do a lot more than build UIs.

In this guide, @devseyi shows you how to build and ship production REST APIs with Dart and Shelf.

You'll connect PostgreSQL, add JWT auth and middleware, containerize with Docker, and deploy the API to https://t.co/dtd5MLkj9i.

https://t.co/DbsMMz4RmI

[freeCodeCamp.org @freeCodeCamp]

Staging uploads shouldn't keep adding to your production cloud storage bill.

So in this guide, @MDTARIK46263152 shows you how to self-host an S3-compatible object store with MinIO, Docker Compose, and Traefik.

You'll keep the same upload code while adding HTTPS, custom domains, presigned URLs, CORS, backups, and monitoring.

https://t.co/T5xSZBc83Z

[freeCodeCamp.org @freeCodeCamp]

For today's coding challenge, you'll again be trying to figure out if an object (JS) or dictionary (Python) matches a particular schema - a bit more complex than the last ones. Check it out on the freeCodeCamp mobile app.

[freeCodeCamp.org @freeCodeCamp]

AI support agents shouldn't try to answer every ticket.

In this guide, @TechWithRJ2 shows you how to build an AI support agent that escalates risky cases instead of guessing.

You'll use a pure-function decider, grounded drafting, consensus verification, caching, and observability to make support automation safer.

https://t.co/Xy5h8hdjNd

[freeCodeCamp.org @freeCodeCamp]

Two smartwatches can track the same walk and still report very different step counts.

Why? Well here, Shradha explains how wearables use accelerometers, gyroscopes, and algorithms to estimate your steps.

You'll learn why and how wrist movement, walking speed, false steps, and brand-specific models can all affect the final number.

https://t.co/86UodQy8PS

[freeCodeCamp.org @freeCodeCamp]

When you're working with a PDF - like a contract, report, or manual - page numbers really help.

In this tutorial, @allinonetools shows you how to build a browser-based PDF page numbering tool with JavaScript and PDF-lib.

You'll add PDF uploads, page previews, custom positions, and more - all running locally for better privacy and faster processing.

https://t.co/DRBRyP7rOB

[freeCodeCamp.org @freeCodeCamp]

The AI infrastructure boom goes far beyond NVIDIA and GPUs.

In this guide, Nikhil shows you how to use Python and EODHD data to map where AI capex actually flows.

You'll analyze chips, servers, networking, data centers, power, and more to see where the market has already reacted.

https://t.co/KEDnfXk2ER

[freeCodeCamp.org @freeCodeCamp]

RAG systems can fail when chunks lose the context that makes them meaningful.

To help combat this, @rishi_raj_jain_ explains how contextual embeddings and hybrid search improve retrieval accuracy.

You'll learn how to use smarter chunking, BM25, vector search, reranking, metadata, and graph-based retrieval to reduce hallucinations.

https://t.co/vakgLEaRp1

[freeCodeCamp.org @freeCodeCamp]

Every production team wants to ship faster, but too much infrastructure flexibility can slow everything down.

In this article, @manishmshiva explains why custom platforms, endless configuration, and hasty architecture decisions create drag.

You'll also learn how simpler defaults, fewer decisions, and PaaS-style workflows can help your teams ship and learn faster.

https://t.co/efrWDbYfUQ

[freeCodeCamp.org @freeCodeCamp]

Today's coding challenge is another schema validator. Check it out on the freeCodeCamp mobile app.

[freeCodeCamp.org @freeCodeCamp]

HTML has always supported streaming, but updates still usually happen in document order.

In this detailed guide, @sumit_analyzen explains how Declarative Partial Updates could let browsers patch streamed HTML into specific page regions.

Along the way, you'll learn how placeholders, templates, out-of-order streaming, and new HTML insertion APIs work.

https://t.co/U1a8ZRghGB

[freeCodeCamp.org @freeCodeCamp]

Basic web scrapers often break as soon as they hit CAPTCHAs, IP bans, or 403 errors.

In this course, Gavin teaches you how to build production-ready web scrapers that work on modern websites.

You'll use Playwright, Cheerio, residential proxies, and a MERN dashboard to scrape and visualize live data.

https://t.co/okNzAZEIWZ

[freeCodeCamp.org @freeCodeCamp]

Sometimes deep learning models fail because of the data, not the architecture.

In this article, Lakshmi walks you through how she diagnosed a medical imaging model that struggled to learn.

You'll learn how to check dataset composition, subject leakage, label quality, synthetic-to-real gaps, plus when to stop tuning.

https://t.co/6PF5Up0I4V

[freeCodeCamp.org @freeCodeCamp]

Wearable fall detection can help people get help faster after an emergency.

In this article, Shradha explains how IoT devices use sensors, algorithms, and alerts to detect falls in real time.

You'll learn how accelerometers, gyroscopes, edge processing, ML models, GPS, and caregiver notifications work together in these devices.

https://t.co/G0SvLiBBS3

[freeCodeCamp.org @freeCodeCamp]

You can now build and deploy full websites and mobile apps using natural language.

In this course by @beaucarnes, you’ll learn how to use @ManusAI to create landing pages with SEO, integrate Stripe for payments, and even publish to app stores.

It’s a great deep dive into the world of agentic development.

#aiagent

https://t.co/v2IL0QcsDK

[freeCodeCamp.org @freeCodeCamp]

The open source community offers devs many opportunities to collaborate, learn, & grow.

Contributing to OSS helps you develop skills, get key experience when job hunting, and so on.

If you want to dive in, this course will teach you how to get involved.

https://t.co/EYRfb2WVB0

[freeCodeCamp.org @freeCodeCamp]

For today's coding challenge, you'll get an object (JavaScript) or a dictionary (Python). You'll need to determine if it matches a particular schema. See if you can solve it on the freeCodeCamp mobile app.

[freeCodeCamp.org @freeCodeCamp]

In 1958, Frank Rosenblatt built the first perceptron. It's basically the ancestor of all neural networks.

And in this tutorial, @PlaybackPress recreates that experiment using modern Python to help you learn ML fundamentals.

You’ll walk through a rule-based solution and then see a learning perceptron in action.

https://t.co/1EbQt5sA14