Open to opportunities

Xavier-Khalil Mas

@xavier-khalilmas

Message

Senior WordPress & full-stack engineer scaling secure, high-performance WordPress platforms with React.

United States

Message

What I'm looking for

I’m looking for a role where I can architect and scale enterprise WordPress platforms—modernizing Gutenberg/headless builds, improving Core Web Vitals, and strengthening security and production reliability with a collaborative engineering team.

I’m a Senior WordPress & Full-Stack Engineer with 7+ years designing, scaling, optimizing, and supporting enterprise WordPress ecosystems across SaaS, healthcare, finance, education, digital publishing, and eCommerce. I specialize in modern WordPress engineering that keeps editorial workflows fast, reliable, and secure.

In my recent role, I architected high-availability WordPress platforms and engineered scalable Gutenberg block systems using React, JavaScript, and PHP. I build advanced custom themes and plugin ecosystems with hooks and filters, WP REST API integrations, and frontend component systems—plus WooCommerce transactional solutions with Stripe, subscriptions, dynamic pricing, and conversion-focused checkout experiences.

I’m deeply hands-on with performance and reliability: I lead Core Web Vitals work (lazy loading, asset pipeline optimization, semantic HTML improvements, image compression, browser caching, CDN tuning) and implement caching strategies with reverse proxy optimization, Cloudflare, object/transient caching, and MySQL query tuning.

I also strengthen security and operations by applying OWASP-aligned protections (XSS, CSRF, insecure authentication, SQL injection, API security weaknesses) and performing deep production debugging using WP-CLI, browser profiling, and incident-focused root-cause analysis. I enjoy mentoring and collaborating across distributed teams to modernize frontends, coordinate deployments, and deliver customer-facing engineering improvements.

Experience

Work history, roles, and key accomplishments

Senior WordPress & Full-Stack Engineer

BairesDev

Oct 2024 - Feb 2026 (1 year 4 months)

Architected and maintained enterprise-grade WordPress ecosystems with secure, high-availability production requirements for SaaS and financial services. Led Gutenberg, REST API integrations, WooCommerce subscription and payments workflows, Core Web Vitals optimization, caching, and OWASP-aligned security, and mentored junior engineers.

WordPress React PHP WooCommerce REST APIs WooCommerce Stripe Subscriptions

Senior WordPress Engineer

Temper and Forge

Jan 2022 - Oct 2024 (2 years 9 months)

Delivered enterprise WordPress solutions across SaaS, education, retail, and digital publishing using Gutenberg, React, and WooCommerce. Improved Lighthouse and Core Web Vitals through frontend optimization, managed Linux/Nginx hosting with Cloudflare/CDN, and resolved production incidents including plugin conflicts and REST API failures.

WordPress Gutenberg React WooCommerce Linux Nginx Cloudflare Performance Optimization (Lighthouse Core Web Vitals)

WordPress Full-Stack Developer

Empat

Jun 2020 - Oct 2022 (2 years 4 months)

Built scalable WordPress and WooCommerce applications for education and corporate learning platforms, focusing on dynamic content management and transactional workflows. Developed custom post types and reusable plugins, implemented responsive React-based frontend components and REST API integrations, and improved reliability via query optimization, caching, and CDN support.

WordPress WooCommerce Custom Post Types Taxonomies Gutenberg React REST APIs Caching Strategies

Frontend & WordPress Developer

PopArt Studio

May 2019 - May 2020 (1 year)

Developed responsive WordPress websites and marketing experiences, converting Figma/PSD assets into pixel-perfect themes optimized for accessibility, SEO performance, and cross-browser compatibility. Built reusable landing-page and UI component systems with analytics and CRM-integrated marketing workflows, and handled ongoing WordPress maintenance and deployments.

PHP JavaScript Bootstrap Responsive Web Design Accessibility

Junior Web Developer

Vardot

Jun 2018 - Apr 2019 (10 months)

Assisted with developing and maintaining WordPress CMS platforms for nonprofit and small business clients, implementing theme enhancements, reusable plugin functionality, and PHP-based customizations. Supported deployments and hosting operations (SSL/DNS/backups), and troubleshot plugin conflicts, rendering/layout issues, and WordPress update defects using Linux, Nginx, and Apache server knowledge

WordPress PHP Custom Theme Development Plugin Development Nginx SSL DNS Deployment Production Troubleshooting