Developer Hub
From coding basics to software architecture, from dev tools to engineering practice — build your tech stack systematically
Tech Blog
Hands-on experience and deep technical exploration
Programming Languages
Learn mainstream programming languages systematically
Python in 21 Days
From zero to Python mastery with interactive lessons
Java Quick Start
Master Java syntax and OOP in 14 days
C# Quick Start
Master C# and .NET core concepts in 14 days
C Language (60 Days)
A 60-day systematic course from syntax to pointers and memory
Dev Tools & Databases
Essential tools and data storage for real projects
Git Quick Start
Version control, branching and team collaboration in 7 days
VSCode Icebreaker
Level up your editor and workflow in 14 days
MySQL Tutorial
21 lessons from SQL syntax to query optimization
FastAPI in 7 Days
Master FastAPI from routing to async programming in 7 days
Software Engineering
Master software engineering methodology systematically
System Planning & Analysis
IS planning, requirements analysis and system design
Software Requirements
Requirements elicitation, modeling, validation and management
Project Management
Scope, schedule, cost, quality, risk and configuration management
Software Engineering
Process models, design methods, testing and quality management
Software Architecture
Architectural styles, quality attributes, distributed and cloud-native
Software Design
Structured design, OO design, design patterns and UML
Online Dev Tools
A toolbox for development, debugging and efficiency
JSON Formatter
One-click validation and custom indentation
Encoding Converter
Convert between text encodings for debugging
Python Code Demo
Run Python online with colorful demos
PNG to ICO
Convert PNG to ICO online, multiple sizes
Keyboard Listener
Show live keystrokes with history
Media & Design Tools
Creation and content production tools
Graphic Design
Design social media images with custom layouts
Background Designer
Social media background generator with Mesh / low-poly themes
Video Composer
Camera background + screen overlay, real-time and recordable
Screen Recorder
Record your screen and camera online
Screenshot
Full-screen or region capture with one-click save
Voice Recorder
Record, play and download audio online
Special Effects
Curated visual effects: fireworks, matrix rain and more
Gesture Board
Real-time gesture drawing board