Web Development Best Practices

Comprehensive guide to building secure, performant, and accessible web applications

Security First Performance

Security Best Practices

Protect your applications and users with these essential security measures.

🔒 Input Validation & Sanitization

Critical

Always validate and sanitize user input to prevent injection attacks.

  • Validate on both client and server side
  • Use allowlists instead of blocklists
  • Escape output to prevent XSS
  • Use parameterized queries for databases
// Good: Server-side validation
function validateEmail(email) {
    const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
    return emailRegex.test(email) && email.length <= 254;
}

// Sanitize HTML output
function sanitizeHTML(input) {
    const div = document.createElement('div');
    div.textContent = input;
    return div.innerHTML;
}

🛡️ Security Headers

Critical

Implement comprehensive security headers to protect against common attacks.

  • Content Security Policy (CSP)
  • X-Content-Type-Options: nosniff
  • X-Frame-Options: DENY
  • X-XSS-Protection: 1; mode=block
  • Strict-Transport-Security (HSTS)
<!-- Security Headers Example -->
<meta http-equiv="Content-Security-Policy" 
      content="default-src 'self'; script-src 'self' 'unsafe-inline';">
<meta http-equiv="X-Content-Type-Options" content="nosniff">
<meta http-equiv="X-Frame-Options" content="DENY">
<meta http-equiv="X-XSS-Protection" content="1; mode=block">

🔐 Authentication & Authorization

High

Implement secure authentication and proper authorization controls.

  • Use strong password policies
  • Implement multi-factor authentication (MFA)
  • Use secure session management
  • Implement proper role-based access control (RBAC)
  • Never store passwords in plain text

🔍 Dependency Management

High

Keep dependencies updated and scan for vulnerabilities.

  • Regularly update dependencies
  • Use automated vulnerability scanning
  • Remove unused dependencies
  • Use dependency lock files
  • Monitor security advisories

Performance Best Practices

Optimize your applications for speed and efficiency.

⚡ Core Web Vitals

High

Optimize for Google's Core Web Vitals metrics.

  • LCP (Largest Contentful Paint): < 2.5s
  • FID (First Input Delay): < 100ms
  • CLS (Cumulative Layout Shift): < 0.1
// Optimize images for LCP
<img src="hero.jpg" 
     alt="Hero image" 
     loading="eager" 
     width="800" 
     height="600">

// Defer non-critical JavaScript
<script src="analytics.js" defer></script>

📦 Asset Optimization

Medium

Optimize your assets for faster loading.

  • Compress images (WebP, AVIF)
  • Minify CSS, JavaScript, and HTML
  • Use CDN for static assets
  • Implement lazy loading
  • Use modern image formats

🚀 Caching Strategies

Medium

Implement effective caching to reduce load times.

  • Browser caching with proper headers
  • CDN caching for static assets
  • Service worker caching
  • Database query caching
  • API response caching

📱 Mobile Optimization

Low

Ensure your application works well on mobile devices.

  • Responsive design principles
  • Touch-friendly interface elements
  • Optimize for mobile networks
  • Test on real devices

Accessibility Best Practices

Make your applications usable by everyone, including users with disabilities.

♿ WCAG Compliance

Critical

Follow Web Content Accessibility Guidelines (WCAG) 2.1 AA standards.

  • Provide alternative text for images
  • Use semantic HTML elements
  • Ensure keyboard navigation
  • Maintain sufficient color contrast
  • Provide focus indicators
<!-- Good: Semantic HTML -->
<button aria-label="Close dialog">×</button>
<img src="chart.jpg" alt="Sales chart showing 25% growth">
<nav aria-label="Main navigation">
  <ul>
    <li><a href="/home">Home</a></li>
  </ul>
</nav>

🎯 Focus Management

High

Ensure proper focus management for keyboard users.

  • Visible focus indicators
  • Logical tab order
  • Skip links for navigation
  • Focus trapping in modals

🔊 Screen Reader Support

Medium

Optimize for screen reader users.

  • Use ARIA labels and descriptions
  • Provide live regions for dynamic content
  • Use proper heading hierarchy
  • Test with actual screen readers

SEO Best Practices

Optimize your content for search engines and users.

🔍 Technical SEO

High

Implement technical SEO fundamentals.

  • Proper HTML structure and semantics
  • Meta tags (title, description, keywords)
  • Structured data markup
  • XML sitemaps
  • Robots.txt file
<!-- SEO Meta Tags -->
<title>Web Development Best Practices | Robert Consulting</title>
<meta name="description" content="Comprehensive guide to web development best practices...">
<meta name="keywords" content="web development, best practices, security">

<!-- Structured Data -->
<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "Article",
  "headline": "Web Development Best Practices"
}
</script>

📝 Content Optimization

Medium

Create SEO-friendly content.

  • Use descriptive, keyword-rich headings
  • Write compelling meta descriptions
  • Optimize images with alt text
  • Create internal linking structure
  • Use schema markup

Code Quality Best Practices

Write maintainable, scalable, and reliable code.

📋 Code Standards

High

Follow consistent coding standards and conventions.

  • Use ESLint, Prettier for JavaScript
  • Follow style guides (Airbnb, Google)
  • Use TypeScript for type safety
  • Write self-documenting code
  • Use meaningful variable names

🧪 Testing

High

Implement comprehensive testing strategies.

  • Unit tests for individual functions
  • Integration tests for component interaction
  • End-to-end tests for user workflows
  • Accessibility testing
  • Performance testing

📚 Documentation

Medium

Maintain comprehensive documentation.

  • API documentation
  • Code comments for complex logic
  • README files with setup instructions
  • Architecture decision records (ADRs)
  • User guides and tutorials

Modern Development Practices

Stay current with modern web development trends and tools.

🔄 DevOps & CI/CD

High

Implement modern DevOps practices.

  • Automated testing and deployment
  • Infrastructure as Code (IaC)
  • Containerization with Docker
  • Monitoring and logging
  • Version control best practices

🌐 Progressive Web Apps

Medium

Build modern, app-like web experiences.

  • Service workers for offline functionality
  • Web app manifests
  • Push notifications
  • App-like navigation
  • Installable web apps

⚡ Performance Monitoring

Medium

Monitor and optimize application performance.

  • Real User Monitoring (RUM)
  • Core Web Vitals tracking
  • Error tracking and reporting
  • Performance budgets
  • Automated performance testing

Implementation Checklist

Use this checklist to ensure your projects follow best practices.

🔒 Security Checklist

⚡ Performance Checklist

♿ Accessibility Checklist

🔍 SEO Checklist