Hello I'm
Thomas Kalyvas
Senior Full-Stack Web Developer
Highly experienced Web Developer with over 25 years of expertise in web development and programming, specializing in PHP, MySQL, and modern web technologies.
thomas kalyvas
thomas kalyvas
About

Highly experienced Web Developer with over 25 years of expertise in web development and programming, specializing in PHP, MySQL, and modern web technologies.

Proven track record of delivering high-quality web solutions, with hundreds of completed projects and collaborations with prominent Greek and international clients.

Adept in clean, well-documented coding practices and advanced API integrations, including ERP systems, booking platforms, and payment gateways.

I can create or update addons, plugins and modules for all popular CMS (Wordpress, Cs-cart, Prestashop etc).

Name

Thomas Kalyvas

Phone

+30 6945 899 399

Email

grjava@yahoo.com

Address

Chalandri, Attiki, Greece

Languages

Greek | English

Available

Freelance | Αs an employee

Services
PHP & MySql

Experienced in designing, developing, and optimizing data-driven web applications. Expertise spans custom PHP and MySQL implementations, complemented by strong proficiency in leading PHP frameworks like Laravel, Smarty, Symphony for complex project delivery. LAMP environment, Design Patterns, Object Oriented programming.

CMS & E-commerce

Adept at comprehensive e-commerce and content management solutions. I've delivered excellent results with WordPress-WooCommerce, CS-Cart, and PrestaShop, and have strong proficiency in OpenCart. A key strength lies in my ability to design, develop, and maintain custom plugins, modules, and add-ons that seamlessly integrate and expand core platform features.

Javascript & Ajax

Adept at enhancing user experience and website functionality using client-side JavaScript and AJAX techniques. Extensive experience with the jQuery library for streamlined development of dynamic content and efficient data communication.

HTML & CSS

Strong foundational skills in semantic HTML5 and modern CSS3 for creating visually stunning and responsive web interfaces. Comprehensive experience with popular CSS preprocessors and frameworks (e.g. Tailwind CSS, Less, Sass) to optimize development and ensure scalable design systems.

APIs (REST & SOAP)

Comprehensive experience in technical project management and system architecture. Expert in developing and managing APIs (REST & SOAP) to facilitate complex data flow and integration for enterprise-level applications, including ERP, Booking, and Payment gateway systems.

SEO & Website speed

Experienced in implementing technical SEO best practices and advanced website speed optimization techniques. Adept at analyzing performance metrics and leveraging tools to reduce load times, improve Core Web Vitals, and boost search engine rankings.

Resume
Work Experience
January 2024 – February 2025

Senior Web Developer

Wild Wild Web, Argyroupoli, Athens

  • Developed custom PHP solutions and WordPress/WooCommerce applications.
  • Created and maintained CMS plugins and modules, ensuring high performance and security.
June 2021 – December 2023

Lead Web Developer

Cs Cart Biz, Marousi, Athens

  • Spearheaded backend development for Cs-Cart and Prestashop projects and custom PHP solutions.
  • Designed and implemented scalable e-commerce platforms and APIs.
November 2019 – June 2021

Senior Web Developer

Eshoped, Piraeus

  • Customized and optimized CMS solutions for Prestashop and WordPress platforms and custom PHP solutions.
  • Delivered robust backend solutions for diverse client projects.
January 1997 - Present

Freelance Web Developer

My own business, Athens, Greece

  • Independently developed over 200 websites and contributed to 500+ projects.
  • Specialized in backend development and plugin/module creation for various CMS and custom PHP solutions.
My Education
June 2024

Open University Student OF SCIENCE & TECHNOLOGY

Athens, Greece MBA

June 1989

The Athens University of Economics

Athens, Greece MBA

Latest Projects
These works represent a selection of my latest projects. In total, I have either contributed to or solely developed more than 1000 projects.

Shopflix.gr

Lead backend developer for a Cs-Cart Multi-Vendor marketplace. I have created a custom API system for vendors and a payment method for clients/vendors.

Seajets.com

Senior backend developer for a travel website using WordPress-WooCommerce. I have created an online booking system.

Navihellas.gr

Full-stack developer for a custom cruise website. I have created a booking system by parsing SOAP and Rest APIs from various cruise companies.

Neonyxcruises.com

Senior backend developer for a cruise booking website using WordPress-WooCommerce. I have created the booking system for cruises and events/excursions.

E-selides.gr

Full-stack developer for an educational portal. I have created a security system for upload- download education lessons.

Print-photos-online.com

Full-stack developer for a CS-Cart eshop. I have created a system for migrate with Mediaclip API.

Contact
Get In Touch
Have a question or want to discuss a project? Send us a message!
grjava@yahoo.com
+30 6945 899 399
Chalandi, Attiki, Greece