e-learning
Personal tutoring, reimagined.
Agent-native Learning Companion that grows with you. Fully Open-Sourced.
Furigana, set by the font.
Furifont is a Japanese font that shows furigana on the font itself. With the ligatures to adopt to pronunciation of words. Works everywhere supporting custom fonts.
Master Claude Code in a Weekend
Go from typing claude to orchestrating agents, hooks, skills, and MCP servers — with visual tutorials, copy‑paste templates, and a guided learning path.
A deliberately vulnerable Microsoft Entra ID environment. Learn identity security through hands-on, realistic attack challenges.
EntraGoat is a deliberately vulnerable Microsoft Entra ID infrastructure for security professionals. Deploy real-world identity misconfigurations and privilege escalation paths in your own tenant, then practice exploiting them in a safe, black-box CTF format.
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The Complete Reference. Every CSS unit, explained.
From the everyday px and rem to the fine print ofsvh, dvh and cqi: all 63 of them, with live examples wherever seeing beats reading.
How an LLM Works, as a City.: A language model laid out as a city, one token at a time.
TokenTown is an isometric city where every district is one stage of a transformer language model. A convoy carries a hidden state along the roads: it is cut into tokens at the docks, cast into a vector at the foundry, stamped with its position, then driven around the layer ring (attention, residual, feed-forward, residual) once per layer, before the stadium turns it into a probability distribution and the sampler picks one token. That token drives back up the feedback highway and the whole city runs again.
DevSecOps XL Labs CLI.
Turn declarative exercises into reproducible, runnable and verifiable lab environments.
dsoxlab turns declarative exercises into reproducible, runnable and verifiable environments. A catalog states what it offers through a root meta.yml and one lab.yaml per lab; the engine provisions what each lab asks for, opens it, and proves the result with tests that read the state of the system rather than the commands typed into it.
10 Weeks, 20 Lessons, Data Science for All!
Azure Cloud Advocates at Microsoft are pleased to offer a 10-week, 20-lesson curriculum all about Data Science. Each lesson includes pre-lesson and post-lesson quizzes, written instructions to complete the lesson, a solution, and an assignment. Our project-based pedagogy allows you to learn while building, a proven way for new skills to 'stick'.
This is an online edition of the classic technical reference Five Hundred and Seven Mechanical Movements by Henry T. Brown.
This site contains the original illustrations and text from the 21st edition of the book, published in 1908. It also includes animated versions of the illustrations, and occasional notes by the webmaster.
A compilation of challenges that aims to provide practice in simple to advanced concepts in the following topics: Digital Forensics, Incident Response, Malware Analysis and Threat Hunting.
This is aimed at Professionals, Security Researchers, Students, CTF Players as well as DFIR & Malware Analysis Enthusiasts in the field of Cyber Security who want to practice or have an interest in the aforementioned topics.
Understand AI systems visually.
An interactive atlas of agent architectures, safety patterns, evals, context systems, and coding agents — drawn as living diagrams instead of prose.
An interactive, physically grounded model of the solar system that demonstrates how gravity shapes orbits — built with TypeScript + Three.js + Vite.
It opens with a guided, 24-step walkthrough and then hands you a free-explore mode. Everything is driven by real astronomical data; the only thing the renderer ever fakes is the scale (and that is a toggle you control).
(Being a Short Treatise on the Nature of Failure; How Failure is Evaluated; How Failure is Attributed to Proximate Cause; and the Resulting New Understanding of Patient Safety)
Learn to build AI agents locally without frameworks
Understand what happens under the hood before using production frameworks. Build real understanding of function calling, memory, and ReAct patterns.
How PostgreSQL Works, in 3D.
PGSimCity is an independent, non-commercial educational visualization of PostgreSQL internals. It is not affiliated with, sponsored, endorsed, or approved by Electronic Arts Inc. SimCity is a trademark of Electronic Arts Inc.
Magical Rust patterns laid out and simplified.
The best way to learn Rust is by looking at simplified examples and building from there. Well, maybe not the best way, but this is the content of this blog repository.
extensive tutorial resource for learning Modern OpenGL.
Welcome to the online book for learning OpenGL! Whether you are trying to learn OpenGL for academic purposes, to pursue a career or simply looking for a hobby, this book will teach you the basics, the intermediate, and all the advanced knowledge using modern (core-profile) OpenGL. The aim of LearnOpenGL is to show you all there is to modern OpenGL in an easy-to-understand fashion with clear examples, while also providing a useful reference for later studies.
How well do you know JavaScript's Date class?
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A game where you are a computer's OS and you have to manage processes, memory and I/O events.
This is a game where you are the operating system of a computer. As such, you have to manage processes, memory and I/O events. Make sure not to leave processes idling for too long, or the user will get really impatient and reboot you!
Labs 100% Locaux & Dockerisés.
Projet support pour les labs des Mini-classes Ansible, partagé avec tout le monde.
One color a day, told as it ought to be told: with its provenance, its chemistry, and the people who paid for it in poison.
Welcome to the Fintech Engineering Handbook. This resource aims to describe the most important patterns used in software engineering, where money is the primary focus of the system. It can be read in full to get a comprehensive understanding or in parts when dealing with a particular problem.
A comprehensive 2026 guide to Open-Source Intelligence (OSINT): tools, methodologies, ethics, and techniques for responsible research and investigation.
Learn how to use Claude for everyday work tasks, understand core features, and explore resources for more advanced learning on other topics.
Pick the guide that matches your background.
Beginner, advanced, expert level Rust training material.
An experiment in using LLMs to teach you, rather than think for you.
Lathe generates hands-on, multi-part technical tutorials on demand, with skills tuned to make content approachable. Then you work through them yourself, by hand, in a local UI built from the ground up for pleasant learning. (Just like we did it in the stone age 😎)
Learn Branches, Commits, Staging and Remotes.
Practice Git in an interactive browser terminal with a visual repository model. Learn the working directory, staging area, local commits, branch pointers, remotes, fast-forward merges, fetch, and rebase.
Containerized Learning Environment Ansible-HandsOn is a lightweight local lab environment designed for learning, testing, and mastering Ansible infrastructure automation.
Instead of relying on resource-heavy Virtual Machines (VMs), this project leverages Docker containers to simulate a real-world network infrastructure in seconds.
a free educational game that's inspired by Netflix's Squid Game, SQL Murder Mystery, and a few other SQL Games we love to play.
PATTERN MATCHING DEFENSE. Write regex patterns to destroy falling strings.
20 questions from easy to hard to test your RGB knowledge. How far will you go?
A collection of notebooks/recipes showcasing some fun and effective ways of using Claude.
The Claude Cookbooks provide code and guides designed to help developers build with Claude, offering copy-able code snippets that you can easily integrate into your own projects.
A complete walkthrough of how large language models like ChatGPT are built — from raw internet text to a conversational assistant. Based on Andrej Karpathy's technical deep dive.
15-stage Windows malware development & analysis course in Rust. Red team builds it, blue team detects it. All 15 binaries achieved 0/76 on VirusTotal.
The Origami Store is a Devops Learning App created by School of Devops.
a Polyglot, Micro-Services based application, built with the Modern Tech stack, specially designed to be used as a learning app to buid Devops Projects with.
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It's an AI teacher that lives as a buddy next to your cursor. It can see your screen, talk to you, and even point at stuff. Kinda like having a real teacher next to you.
A 30-minute talk sharing practical lessons from building real production projects with AI coding agents — from brainstorming to shipped code.
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A ~9M parameter LLM that talks like a small fish.
This project exists to show that training your own language model is not magic. No PhD required. No massive GPU cluster. One Colab notebook, 5 minutes, and you have a working LLM that you built from scratch — data generation, tokenizer, model architecture, training loop, and inference. If you can run a notebook, you can train a language model.
Clock associating time with historical or mathematical facts.
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🎆Interactive Online Platform that Visualizes Algorithms from Code.
Welcome to Algorithm Visualizer, an interactive online platform designed to bring algorithms to life through visualization. Whether you're a student, teacher, or professional, our platform provides an engaging way to explore and understand various algorithms.
Node for Offline Media, Archives, and Data.
Project N.O.M.A.D, is a self-contained, offline survival computer packed with critical tools, knowledge, and AI to keep you informed and empowered—anytime, anywhere.
Complete guide explaining how to build and run a virtualized small Kubernetes cluster with a single Proxmox VE standalone node on a single computer.
p5.js is a friendly tool for learning to code and make art. It is a free and open-source JavaScript library built by an inclusive, nurturing community. p5.js welcomes artists, designers, beginners, educators, and anyone else!
p5.js is a client-side JS platform that empowers artists, designers, students, and anyone to learn to code and express themselves creatively on the web. It is based on the core principles of Processing.
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Learn Terminal Commands Interactively.
A learning environment to master terminal basics.
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Lab4PurpleSec is a modular Purple Team homelab combining a vulnerable Active Directory environment (GOAD), a Docker-based web DMZ, pfSense + Suricata, and a Wazuh SIEM. It provides a realistic, open-source training environment for web exploitation, pivoting, Active Directory attacks, and Blue Team detection.
A compiled list of links to public failure stories related to Kubernetes. Most recent publications on top.
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How to design, build, and operate AI agents for infrastructure teams — safely. 13 chapters covering architecture, sandboxing, credentials, change control, observability, and more.
AI agents can write IaC, fix compliance findings, detect drift, review PRs, and respond to incidents — all autonomously. But autonomy without guardrails is a liability. Agents that can terraform apply can also terraform destroy. Agents that read configs can leak secrets. Agents that loop can burn budgets.
This guide covers every architectural decision you need to make when building infrastructure agents — with real patterns, code snippets, multiple alternatives, and the risk framework to evaluate your choices.
Java Evolved. Your Code Can Evolve Too!.
A collection of side-by-side code comparisons showing old Java patterns next to their clean, modern replacements — from Java 8 all the way to Java 25.
A musical ear training game.
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Razzia is a straightforward and open-source clone of the Kahoot! platform, allowing users to host it on their own server for smaller events.
Learn Languages While You Watch. No More Memorizing.
Turn YouTube, Netflix, and Bilibili into your personal language tutor. Just watch naturally, and let AI help you understand and learn new words instantly.
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Postgres Lock Explainer.
From the Postgres community for the Postgres community. An in-depth explainer of locks that prioritizes warm design, demos, and developer stories based on my experience as a support engineer specializing in Postgres.
Exploration 3D Interactive du Système Solaire.
AstroClick est une expérience web éducative qui revisite l'astronomie avec une esthétique pixel-art unique. Conçu pour les curieux de tous âges, ce simulateur interactif permet de voyager de Mercure à Neptune, d'apprendre des faits surprenants et d'accéder à une galerie d'images officielles, dédiée au savoir.
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Most RAG implementations struggle in production because teams focus on model selection and prompt engineering while overlooking the fundamentals: measurement, feedback, and systematic improvement.
This guide presents practical frameworks for building RAG systems that become more valuable over time through continuous learning and data-driven optimization.