Challenge

A company’s WordPress theme had accumulated years of technical debt, including security vulnerabilities flagged in an audit by 84EM and a monolithic codebase that made maintenance difficult.

The theme relied on external CDNs for critical JavaScript libraries, contained orphaned code from legacy systems, and lacked the modular architecture needed for efficient ongoing development.

Solution

84EM implemented a comprehensive theme modernization initiative addressing security, architecture, and performance.

The project began with security hardening to address vulnerabilities identified in the site audit, followed by a complete restructuring of the theme’s codebase.

A three-phase orphaned code cleanup removed legacy systems that modern solutions had replaced.

Technical Implementation

• Fixed reflected XSS vulnerabilities by adding proper output escaping to all shortcodes and dynamic content.
• Implemented input sanitization across all AJAX handlers to prevent malicious data injection.
• Added prepared SQL statements to all database queries for protection against SQL injection.
• Refactored 1,800-line monolithic functions.php into 18 focused modular files organized by purpose.
• Extracted page-specific JavaScript from a 1,290-line common.js into individual modules for conditional loading.
• Replaced external CDN dependencies with self-hosted vendor libraries for improved reliability and caching.
• Removed 9 unused shortcodes in Phase 1 cleanup after auditing usage across all published pages.
• Eliminated legacy job listing system in Phase 2 after migration to third-party HR platform.
• Removed legacy form integration code in Phase 3 following migration to HubSpot forms.

Results

The theme now passes security audits with all XSS, input validation, and SQL injection vulnerabilities resolved.

The modular architecture reduced the main entry file by over 95%, making updates and debugging significantly faster.

Self-hosted assets eliminated third-party CDN dependencies, improving page load reliability and enabling complete control over caching.

The three-phase cleanup removed more than 20 orphaned files, reducing technical debt and improving maintainability.

JavaScript optimization reduced the global script bundle by approximately 80% through page-specific conditional loading.