Valerii Vasyliev | Gratta Studio
Full-Stack Developer
š Hi, I'm Valerii, a senior WordPress and WooCommerce backend developer with 16+ years of PHP. I find the real cause behind slow sites, broken checkouts, failing integrations and recurring malware, then fix it so it stays fixed. I also build custom plugins and run complex migrations.
4.96/5
overall rating
280
projects
117
customers
Location
Valencia, Spain
Languages
English, Russian, Spanish; Castilian, Ukrainian
Member since
13 Jan, 2023
3 years
Typical projects
Full Website Builds, Performance Optimizations, Troubleshooting and Fixes
16+ years of PHP, most of it WordPress and WooCommerce backend work, as a Lead WordPress Developer and at NitroPack on plugin-to-host compatibility. Clients bring me the problems where the cause isn't obvious. I diagnose first, fix the root cause, and then tell you what I changed, what I tested and what I left untouched. WHAT I SOLVE ā” Slow sites: I trace the slowdown to the exact query, hook or plugin, then fix caching, Redis, Cloudflare and the optimization plugins so they work together instead of against each other. š WooCommerce problems that cost sales: checkout and payment gateway failures, order flow bugs, subscriptions, memberships and anything that broke after an update. š”ļø Malware that keeps coming back: I find the backdoor that earlier clean-ups missed, remove it and harden the site so it stays clean. šļø Database trouble: slow queries, bloated tables, crashes and errors that bring the site down. WHAT I BUILD š Custom plugins built the WordPress way, so they survive core, theme and plugin updates. š Integrations: payment gateways, CRMs like HubSpot, REST APIs, webhooks and headless WordPress with Next.js. š¤ AI for WordPress: WordPress Abilities API, MCP servers that let AI agents work with your site, and AI features inside custom plugins. š Migrations from other platforms and membership plugins, plus PHP and WordPress upgrades without breaking what already works. HOW YOU CAN WORK WITH ME ā¢ Diagnosis: a fixed-scope investigation that ends with a clear cause and a fix plan. ā¢ Fixed-price projects: plugins, integrations, migrations, speed work. ā¢ Ongoing care: monthly maintenance or a block of on-demand hours. āļø At home on Cloudways, Kinsta, WP Engine, Pressable, Pantheon, Altis and Cloudflare. I work with WP-CLI and Git so every change is safe and reversible.
Skills
5/5
Is amazing to work with this guy. An amazing professional and very efficient. 10/10
Jul 20, 2023
5/5
We are in very different time zones which meant we were often communicating at different times of the day, but Valerii replied to enquiries very promptly and always gave clear detail in his explanations. I would definitely recommend him to other users.
Jun 12, 2023
5/5
Valerii was great at responding back on the problem and had found initial problems even before being hired. Understood the task and executed with great confidence.
Jun 09, 2023
5/5
I cannot say enough wonderful things about Valerii! I contacted him during an extremely stressful situation when my e-commerce website stopped accepting orders during a major sale. To make matters worse, there were serious security issues that needed immediate attention. From the beginning, Valerii was professional, knowledgeable, patient, and incredibly thorough. He took the time to explain what was happening in terms I could understand, identified the problems, secured my website, and restored my checkout functionality. What impressed me most was his attention to detail, clear communication, and genuine commitment to resolving the issues properly rather than simply applying a temporary fix. As a business owner, having someone you can trust with your website is invaluable. Valerii gave me peace of mind during a very overwhelming experience. Iām extremely grateful for his expertise and excellent service. I would absolutely hire him again and highly recommend him to anyone needing a skilled, dependable WordPress or WooCommerce developer!
Nov 04, 2026
5/5
Thanks for your work looks great!
Oct 26, 2026
5/5
Great communication, customer service skills and professional ability
Jan 12, 2026
5/5
Valeriy was prompt and thorough in responding to queries and completing the work
Nov 25, 2025
5/5
Valeriy delivered outstanding work on a highly complex WordPress performance project for us. Our website suffered from severe performance issues that several developers were unable to identify or resolve. Valeriy not only found the root causes within a very short time, he also implemented targeted optimizations that resulted in a dramatic performance improvement across all metrics, including LCP, TTFB and overall loading stability. What really stands out is his analytical approach and his ability to explain technical matters clearly. He documented every step, worked methodically, and always kept us up to date. The solutions he implemented were clean, scalable and fully in line with best practices. Communication was excellent. He responds quickly, works transparently and is extremely reliable. Even under time pressure he stayed focused and delivered above expectations. We will continue working with him on further performance fine tuning, structural optimizations and a security audit, because we trust his expertise completely. If you are looking for a developer who is both technically brilliant and highly professional in communication and execution, we can recommend Valeriy without reservation.
Nov 20, 2025
5/5
The work was carried out exactly as requested. Valeriy was clear about the task in hand and provided a detailed explanation of the what changes were made and where they were made for future reference.
Nov 19, 2025
5/5
Valeriy was quick to respond and resolve my issue. I would definitely hire him again. Thank You Valeriy!!!
Nov 06, 2025
Restaurant Reservation System Customization
I enhanced a restaurant reservation system with key features like date exclusion for specific events, a cut-off time for same-day reservations, and customizable settings for special business days. These improvements, adaptable for various scenarios and easily managed through a user-friendly interface, significantly streamlining the reservation process.
Stock and Grain
Updated the theme to PHP 8.1 and created new page templates for online ordering and news pages.
Lehigh Valley International Airport (ABE)
Developed an integration with an external API that retrieves real-time data on flight arrivals and departures. This involved creating a system that could effectively communicate with the API and process the data it provided. I designed the integration to be flexible and scalable, allowing for future updates and enhancements as needed.
FarPlay
The task involved creating a custom WordPress plugin that provides a simple Single Sign-On (SSO) solution using PHP sessions. The plugin will create a record in the WordPress database upon user sign-in, based on the PHP session. The goal is to allow users to sign in once and access multiple applications, without having to enter their credentials again.
Vormats
I personally conceptualized and constructed the website for the newly established company, utilizing designs provided by an external agency.
Shopping Roulette
Shopping Roulette presents itself as a comprehensive e-commerce solution, incorporating advanced gamification elements and seamless integration with a multitude of partners.