Free Developer Resources

A curated collection of high-quality guides, cheatsheets, templates, and tools to accelerate your development journey. All resources are free and regularly updated.

Study Guides

Comprehensive study materials for developers at all levels, covering technical interviews, skill development, and career advancement.

Interview Preparation

Technical interviews can be challenging, but proper preparation makes all the difference. These guides cover the most common interview topics and provide practical advice for success.

Coding Challenges

Practice problems ranging from beginner to advanced, with detailed solutions and explanations. Perfect for interview preparation or skill development.

System Design

Learn how to design scalable systems with our comprehensive system design resources. Covers everything from basic concepts to advanced architectural patterns.

🎯 Popular System Design Case Studies:

📚 System Design Topics:

• Core
  Scalability Principles: Horizontal vs vertical scaling, load balancing strategies, auto-scaling policies, and capacity planning methodologies.
• Data
  Data Storage & Management: SQL vs NoSQL databases, database sharding, replication strategies, data partitioning, and backup mechanisms.
• Arch
  Architecture Patterns: Microservices vs monoliths, event-driven architecture, serverless computing, and service mesh implementations.
• Theory
  Trade-offs & Theory: CAP theorem implications, consistency models, eventual consistency, performance vs complexity analysis.

Quick Reference

Handy reference materials for daily development work. These cheatsheets and snippets are designed for quick lookup during coding sessions.

Cheatsheets

Concise reference cards for popular technologies, frameworks, and tools. Perfect for keeping nearby while coding or studying.

Code Snippets

Reusable code snippets for common programming tasks. Save time by copying and adapting these tested solutions to your projects.

// Debounce function for search inputs
function debounce(func, wait, immediate) {
  let timeout;
  return function executedFunction(...args) {
    const later = () => {
      timeout = null;
      if (!immediate) func(...args);
    };
    const callNow = immediate && !timeout;
    clearTimeout(timeout);
    timeout = setTimeout(later, wait);
    if (callNow) func(...args);
  };
}

// Usage example - Search with 300ms delay
const searchHandler = debounce((query) => {
  console.log('Searching for:', query);
  // Perform API call here
  fetch(`/api/search?q=${encodeURIComponent(query)}`)
    .then(response => response.json())
    .then(data => console.log(data));
}, 300);

// Attach to input event
document.getElementById('search')?.addEventListener('input', (e) => {
  searchHandler(e.target.value);
});

// Deep clone function that handles various data types
function deepClone(obj) {
  if (obj === null || typeof obj !== 'object') {
    return obj;
  }
  
  if (obj instanceof Date) {
    return new Date(obj.getTime());
  }
  
  if (obj instanceof Array) {
    return obj.map(item => deepClone(item));
  }
  
  if (typeof obj === 'object') {
    const clonedObj = {};
    for (let key in obj) {
      if (obj.hasOwnProperty(key)) {
        clonedObj[key] = deepClone(obj[key]);
      }
    }
    return clonedObj;
  }
}

// Usage examples
const original = {
  name: 'John',
  details: {
    age: 30,
    hobbies: ['reading', 'coding']
  },
  createdAt: new Date()
};

const copy = deepClone(original);
copy.details.age = 31; // Original remains unchanged

// Local storage with built-in expiration
const storage = {
  set(key, value, expiryInMinutes = 60) {
    const now = new Date();
    const item = {
      value: value,
      expiry: now.getTime() + (expiryInMinutes * 60 * 1000)
    };
    localStorage.setItem(key, JSON.stringify(item));
  },
  
  get(key) {
    const itemStr = localStorage.getItem(key);
    if (!itemStr) return null;
    
    const item = JSON.parse(itemStr);
    const now = new Date();
    
    if (now.getTime() > item.expiry) {
      localStorage.removeItem(key);
      return null;
    }
    
    return item.value;
  },
  
  remove(key) {
    localStorage.removeItem(key);
  }
};

// Usage
storage.set('userToken', 'abc123', 30); // Expires in 30 minutes
const token = storage.get('userToken'); // null if expired

import { useState, useEffect } from 'react';

function useLocalStorage(key, initialValue) {
  const [storedValue, setStoredValue] = useState(() => {
    try {
      const item = window.localStorage.getItem(key);
      return item ? JSON.parse(item) : initialValue;
    } catch (error) {
      console.log(error);
      return initialValue;
    }
  });

  const setValue = (value) => {
    try {
      setStoredValue(value);
      window.localStorage.setItem(key, JSON.stringify(value));
    } catch (error) {
      console.log(error);
    }
  };

  return [storedValue, setValue];
}

// Usage in component
function UserPreferences() {
  const [theme, setTheme] = useLocalStorage('theme', 'light');
  
  return (
    <button onClick={() => setTheme(theme === 'light' ? 'dark' : 'light')}>
      Switch to {theme === 'light' ? 'dark' : 'light'} mode
    </button>
  );
}

import { useState, useEffect } from 'react';

function useFetch(url, options = {}) {
  const [data, setData] = useState(null);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState(null);

  useEffect(() => {
    const fetchData = async () => {
      try {
        setLoading(true);
        const response = await fetch(url, options);
        
        if (!response.ok) {
          throw new Error(`HTTP error! status: ${response.status}`);
        }
        
        const result = await response.json();
        setData(result);
      } catch (err) {
        setError(err.message);
      } finally {
        setLoading(false);
      }
    };

    fetchData();
  }, [url]);

  return { data, loading, error };
}

// Usage in component
function UserProfile({ userId }) {
  const { data: user, loading, error } = useFetch(`/api/users/${userId}`);

  if (loading) return <div>Loading...</div>;
  if (error) return <div>Error: {error}</div>;
  
  return <div>Welcome, {user?.name}!</div>;
}

Project Templates

Kickstart your projects with our curated collection of templates and boilerplates. These templates follow best practices and include essential tooling setups.

Starter Projects

Complete project templates with authentication, database setup, and deployment configuration. Perfect for hackathons, side projects, or learning new technologies.

Boilerplates

Minimal, focused boilerplates for specific use cases. These provide just enough structure to get started without overwhelming complexity.

Developer Tools

Curated list of tools that can improve your development workflow, productivity, and code quality.

Recommended Tools

Browser Extensions

Essential browser extensions for developers, including debugging tools, productivity enhancers, and design utilities.