In Apache configurations, rule processing follows strict first-match-wins semantics. This means:

• RewriteRules execute top-to-bottom until a match occurs
• Headers/modules process directives in declaration order
• Erroneous ordering can cause redirect loops or cache conflicts

# 1. Canonicalization FIRST (prevents duplicate content)
RewriteCond %{HTTP_HOST} ^www\.(.+)$ [NC]
RewriteRule ^(.*)$ https://%1/$1 [R=301,L]

# 2. Static resource handling
<IfModule mod_headers.c>
    # Cache policies before rewrites
</IfModule>

# 3. URL processing
RewriteRule ^(.+)/$ /$1 [R=301,L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^(.*)$ $1.php [L]

Essential patterns:

• Place high-traffic rules first (e.g., www redirects)
• Group related conditions using [OR] flags
• Use [L] (last) flag appropriately

Advanced example with fail-fast logic:

RewriteCond %{REQUEST_URI} ^/static/ [OR]
RewriteCond %{REQUEST_URI} \.(css|js|png)$
RewriteRule .* - [L]

# Remaining rules only process non-static requests

Case Study: This incorrect ordering causes double redirects:

# WRONG:
RewriteRule ^(.*)\.html$ $1.php [L]
RewriteRule ^product/(.*)$ product.php?id=$1 [L]
RewriteCond %{HTTP_HOST} ^www\.example\.com

Solution: Always prioritize host-level redirects before path processing.

These elements are order-independent:

• AddType declarations
• Separate <IfModule> blocks
• Non-conflicting header directives

Key takeaway: Proper ordering can yield 3-9x performance improvements.

1. Document rule purposes with comments
2. Group related rules with separator lines
3. Test changes with curl -I before deployment

# DEBUG example:
curl -IL http://example.com/test-redirect

The Apache server processes .htaccess rules sequentially from top to bottom. This means the order absolutely matters - both for functionality and performance. When rules conflict or overlap, the first matching rule will be executed, potentially making subsequent rules irrelevant.

Here's what I've learned from optimizing dozens of .htaccess files:

• Place most frequently accessed rules first
• Group related rules together
• Put redirects before rewrites
• Move static file handling higher up

Your current .htaccess has good structure but could be improved:

# Recommended optimized order:
RewriteEngine on

# 1. Canonical redirects (www to non-www)
RewriteCond %{HTTP_HOST} ^www\.(.+)$ [NC]
RewriteRule ^(.*)$ http://%1/$1 [R=301,L]

# 2. Static file caching headers
<IfModule mod_headers.c>
    # ... (your existing static file rules)
</IfModule>

# 3. URL rewriting rules
RewriteRule ^(.+)/$ /$1 [R=301,L]
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^(.*)$ $1.php

For high-traffic sites, consider these additional improvements:

# Merge conditions when possible
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^([^/]+)/?$ $1.php [L]

# Disable directory listing globally
Options -Indexes

# Compress certain file types
<IfModule mod_deflate.c>
    AddOutputFilterByType DEFLATE text/html text/css application/javascript
</IfModule>

• Don't use .htaccess at all if you have server config access
• Avoid complex regex when simple pattern matching works
• Remove commented-out rules that aren't being used
• Test changes thoroughly - cached redirects can be tricky

Use tools like ApacheBench to measure the impact of your changes:

ab -n 1000 -c 10 http://yoursite.com/testpage.html

Look for improvements in requests per second and reduced latency after optimizing your .htaccess order.