A curated, structured, and evolving collection of developer cheat sheets, system design notes, workflows, terminal tricks, and real-world engineering learnings.

Every developer Googles the same things again and again.

This repository exists to:

• 🧠 Eliminate repeated Googling
• ⚡ Speed up debugging & development
• 📚 Build a second brain for engineering
• 🤝 Encourage team-wide knowledge sharing
• 🔄 Keep practical notes version-controlled

This is not documentation. This is a developer survival kit.

• 🖥️ Terminal & CLI Cheatsheets
• 🐳 Docker & DevOps Commands
• 🛠️ Git Workflows & Fixes
• 🌐 API & Backend Notes
• ⚛️ Frontend Patterns
• 🧪 Debugging Playbooks
• 🔐 Security Quick References
• 📊 Performance Optimization Tips
• 🧩 Architecture & System Design Notes

"Document once. Reuse forever."

• Keep it practical.
• Keep it minimal.
• Keep it searchable.
• Keep it real-world tested.

If it's not useful in real projects, it doesn't belong here.

git clone https://github.com/Nymphalys/DevNotes.git
cd DevNotes

Browse the markdown files organized by technology or concept.

Use GitHub search or:

⌘ + F

to quickly find what you need.

We welcome contributions from:

• Engineers
• DevOps folks
• Interns
• Students
• Curious builders

• Adding new cheat sheets
• Improving clarity of notes
• Updating outdated commands
• Adding real-world debugging solutions
• Improving structure & categorization

If something is outdated or incorrect:

1. Go to Issues

2. Search if it already exists

3. Open a new issue with:

   • Clear title
   • Context
   • Example if possible

We value clarity over volume.

1. Fork this repository
2. Create a branch

git checkout -b feature/topic-name

3. Make your changes
4. Commit clearly

git commit -m "Add Redis troubleshooting guide"

5. Push and open a PR

• Keep markdown clean and structured
• Use headings consistently
• Add examples wherever possible
• Avoid unnecessary long explanations
• Focus on actionable information

If possible, include:

• Command
• What it does
• When to use it
• Example usage

• Add System Design section
• Add Interview Preparation Notes
• Add Production Incident Playbooks
• Add Cloud (AWS/GCP/Azure) Cheatsheets
• Add Architecture Diagrams

• Developers building real systems
• Teams that want shared knowledge
• Students preparing for tech interviews
• Engineers who hate forgetting commands

If you find this useful:

• Star ⭐ the repository
• Share it
• Contribute
• Improve it

Maintained by: 🔗 nymphalys

MIT License – Feel free to use, modify, and improve.

A strong engineer doesn’t just code. They document, refine, and optimize their thinking.

This repository is a step toward that.