Md. Mehedi Hasan, Developer in Dhaka, Dhaka Division, Bangladesh
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Md. Mehedi Hasan

Bio

Mehedi is a full-stack developer with 13+ years of overall web development experience, starting as a WordPress developer and specializing in the PERN stack since 2019. Skilled in PostgreSQL, Node.js, Express.js, React, Next.js, WordPress theme/plugin development, API architecture, Docker, CI/CD, and cloud infrastructure. Experienced in building scalable SaaS apps, complex web platforms, and production-ready solutions.

Portfolio

Invizo LLC
Node.js, TypeScript, Next.js, PostgreSQL, REST APIs, Docker, GitHub Actions...
The Cardus Institute - Main
WooCommerce, WooCommerce Subscriptions 2, Stripe, Plugin Development, GitHub...
Howirollsports
JavaScript, React, GitHub, CSS, HTML, Full-stack Development, Shopify

Experience

  • API Integration - 12 years
  • Full-stack - 7 years
  • Node.js - 7 years
  • Next.js - 5 years
  • Online Payments - 5 years
  • TypeScript - 5 years
  • Artificial Intelligence (AI) - 2 years
  • DevOps - 2 years

Preferred Environment

REST APIs, Node.js

The most amazing...

...work I’ve done is building scalable SaaS apps, advanced WordPress plugins, APIs, and AI-powered RAG solutions.

Work Experience

Full-stack Developer

2023 - PRESENT
Invizo LLC
  • Led full-stack development at Invizo, building 10+ scalable SaaS applications using PostgreSQL, Node.js, Express.js, React, Next.js, TypeScript, Docker, GitHub Actions, and AWS.
  • Built InvizoCRM, a CRM and affiliate management system for app authors, enabling customer management, affiliate tracking, campaigns, subscriptions, onboarding, logs, and admin workflows.
  • Developed Shopify apps, SaaS products, and WooCommerce plugins that automated business workflows and supported production-ready eCommerce operations.
  • Architected REST APIs connecting front-end, back-end, payment, eCommerce, and automation systems for scalable SaaS platforms.
  • Automated internal systems and workflows, saving management more than 100 hours of manual operational work.
Technologies: Node.js, TypeScript, Next.js, PostgreSQL, REST APIs, Docker, GitHub Actions, Amazon Web Services (AWS), React, GitHub, Cloudflare, Scripting, CSS, HTML, Full-stack Development, Tailwind CSS, HTML5, JSON, Data Structures, Code Review, Vanilla JS

WooCommerce Developer

2025 - 2025
The Cardus Institute - Main
  • Updated custom plugin functionality to make it compatible with WooCommerce subscriptions.
  • Managed and fixed bugs through GitHub. Deployed the functionality to Wpengin.
  • Oversaw plugin launch process, ensuring stable deployment and zero post-release critical issues.
Technologies: WooCommerce, WooCommerce Subscriptions 2, Stripe, Plugin Development, GitHub, Cloudflare, CSS, HTML, Vanilla JS

Senior PHP and WordPress Developer

2025 - 2025
Howirollsports
  • Fixed a hacked WordPress site (Howirollsports) by scanning and cleaning malware across database tables, cache, themes, and plugins.
  • Identified and patched security vulnerabilities in outdated code and configurations, ensuring long-term protection.
  • Oversaw the recovery and relaunch, restoring full site performance and client trust with zero downtime.
Technologies: JavaScript, React, GitHub, CSS, HTML, Full-stack Development, Shopify

WordPress Gutenberg Block Developer (via Toptal)

2022 - 2024
Shop Tutors, Inc.
  • Developed 20+ dynamic blocks from Figma for lendedu.com. Fixed 200+ bugs and improved legacy blocks. Wrote e2e tests with Cypress and Playwright.
  • Managed projects using Jira and GitHub Issues. Communicated through Slack.
  • Oversaw the launch of 20+ new blocks for lendedu.com, fixing all the past issues and increasing the editing and publishing efficiency by 40%.
Technologies: Gutenberg Editor, JavaScript, Ajax, DevOps, Node.js, Themes, React, TypeScript, GitHub, Figma, Fintech, Finance, CSS, HTML, Full-stack Development, Tailwind CSS, HTML5, JSON, Data Structures, Cypress, API Development, Code Review, Vanilla JS

WordPress Developer (via Toptal)

2023 - 2023
The Cardus Institute - Main
  • Developed a custom payment gateway and fixed the existing bug with their site.
  • Tracked the bug using GitHub Issues and maintained communication via Slack.
  • Contributed to the development of a new payment gateway, after which they could sell in different countries, increasing their sell-up to 50%.
Technologies: Stripe, WooCommerce, WooCommerce Subscriptions 2, Online Payments, GitHub, CSS, HTML, Vanilla JS

WordPress/WooCommerce Developer

2023 - 2023
Cardus
  • Developed two add-ons for WooCommerce Memberships and Subscriptions and helped with Salesforce integration.
  • Managed our project via GitHub and used Slack for day-to-day communication.
  • Launched my plugins, selling hundreds of subscriptions.
Technologies: WooCommerce, WooCommerce API, WooCommerce Subscriptions 2, Plugin Development, REST APIs, Back-end, Responsive Web Design (RWD), Online Payments, GitHub, CSS, HTML

PHP / WooCommerce Developer

2023 - 2023
Mood Product Group LLC
  • Expedited the WooCommerce site using the new WooCommerce High-Performance Order Storage (HPOS).
  • Tracked the tasks through ClickUp and version-controlled them using Git and GitHub.
  • Contributed to the new order migration by successfully speeding up a big site with 50,000 members and a large database.
Technologies: MySQL, WooCommerce, Site Speed Optimization, Back-end, GitHub, Figma, CSS, HTML

WordPress Developer

2022 - 2023
The Cardus Institute - Main
  • Developed two add-ons. One for a WooCommerce subscription and another for WooCommerce membership.
  • Tracked and fixed bugs using GitHub Issues and established day-to-day communication with Slack.
  • Added the two plugins into production, and they soon got a few subscription gifting and team membership orders.
Technologies: WooCommerce, WooCommerce Subscriptions 2, WordPress Plugins, Divi, Plugins, API Integration, Back-end, Responsive Web Design (RWD), Online Payments, GitHub, CSS, HTML

WordPress/WooCommerce Developer

2022 - 2022
The Cardus Institute - Main
  • Developed a plugin for WooCommerce membership for the team.
  • Tracked the project in GitHub and reported issues in GitHub.
  • Contributed to this big magazine company with thousands of visitors: many universities are its clients, purchasing and sharing the membership with students.
Technologies: WooCommerce, WooCommerce Subscriptions 2, WordPress Plugins, Divi, Plugins, API Integration, Back-end, Online Payments, GitHub, CSS, HTML

WordPress/WooCommerce Developer

2021 - 2022
Cardus
  • Developed a custom payment gateway plugin for Helcim and WooCommerce. It was a conditional payment gateway based on the region.
  • Contributed to the project that was managed through ClickUp; team communication was conducted through Slack.
  • Served as a WordPress and WooCommerce developer for a company founded in 1974 with a huge audience.
Technologies: Payment APIs, REST APIs, Plugin Development, WordPress API, WooCommerce, eCommerce, Object-oriented Programming (OOP), Front-end Development, Design, Stripe, APIs, Troubleshooting, Full-stack, WooCommerce Subscriptions 2, WordPress Plugins, Divi, Plugins, API Integration, Back-end, Responsive Web Design (RWD), Online Payments, CSS, HTML

Senior Full-stack Developer

2021 - 2021
Handprint
  • Developed a custom job application where candidates can share their interests, skills, experience, preferences, and education.
  • Managed the project and used ClickUp, as well as Git to manage version control.
  • Uploaded files to the server using Filezilla. Also used the WP engine to host the site.
Technologies: MySQL, Ajax, CSS3, jQuery, Advanced Custom Fields (ACF), Plugin Development, WordPress Design, Front-end, WooCommerce, eCommerce, Object-oriented Programming (OOP), Composer, Sass, Front-end Development, Responsive, Design, Stripe, APIs, Payment APIs, Troubleshooting, Full-stack, WordPress Plugins, Plugins, Back-end, Responsive Web Design (RWD), Themes, GitHub, Figma, CSS, HTML

WordPress Developer │QA Engineer

2020 - 2021
Elegant Themes
  • Reviewed third-party themes and plugins that are submitted in the Elegant marketplace.
  • Fixed core issues reported in GitHub and then, having fixed the issues, created a pull request.
  • Created a custom addon and a child theme for Divi.
Technologies: Divi, JavaScript, Gutenberg Editor, Object-oriented Programming (OOP), Composer, NPM, Webpack, Front-end Development, ECMAScript (ES6), Responsive, Design, APIs, Troubleshooting, Full-stack, WordPress Plugins, Plugins, API Integration, Back-end, Responsive Web Design (RWD), Themes, GitHub, CSS

WordPress Back-end Developer

2020 - 2020
Kneebouncers
  • Developed a game module for kids where the children can learn the alphabet via a fun activity. There are many features. Free users can access and play free games with advertisements throughout the game.
  • Developed functionality with themes for children, using Filezilla to push the code to the server.
  • Attracted many users to this live game module, contributing to rising active subscriptions.
Technologies: Ajax, jQuery, WooCommerce, WooCommerce Subscriptions 2, Stripe, eCommerce, Object-oriented Programming (OOP), Front-end Development, Responsive, Design, Gutenberg Editor, Payment APIs, Troubleshooting, Search Engine Optimization (SEO), Full-stack, WordPress Plugins, Plugins, Back-end, Responsive Web Design (RWD), CSS

Founder and Lead WordPress | WooCommerce Developer

2017 - 2019
Code4webs
  • Led the team that developed and contributed to more than 1,500 jobs.
  • Tracked and fixed bugs through the FTP and cPanel.
  • Utilized the WordPress admin dashboard to track and resolve bugs.
Technologies: JavaScript, WooCommerce, Advanced Custom Fields (ACF), WooCommerce API, WooCommerce Subscriptions 2, MySQL, CSS3, WordPress Design, Search Engine Optimization (SEO), Full-stack, WordPress Plugins, Plugins, API Integration

WordPress and WooCommerce Expert

2017 - 2019
animalchiropracticeducation.com
  • Developed an online learning management system where students could easily enroll in the course; it was the best online animal chiropractor school.
  • Fixed bugs that were listed in the log file of the WordPress/WooCommerce website.
  • Received a certificate of completion after completing the course.
Technologies: Ajax, jQuery, JavaScript, WooCommerce, eCommerce, Search Engine Optimization (SEO), Full-stack, WordPress Plugins, Learning Management Systems (LMS), Plugins, API Integration, Back-end, Responsive Web Design (RWD), Mailchimp

Experience

Zoyokids Headless eCommerce Store Using Next.Js

https://zoyokids.com
I developed and optimized a high-performance, premium headless storefront for ZoyoKids, a modern eCommerce store for kids' toys and gadgets.

As the lead front-end engineer, I built the application using Next.js 16 (App Router), React 19, and Tailwind CSS. I successfully connected the storefront to a headless WordPress and WooCommerce back end using a hybrid data layer of REST APIs and GraphQL. My role involved implementing a fully responsive, kid-friendly design utilizing Swiper.js for product carousels and Shadcn layout primitives.

KEY CONTRIBUTIONS
• Built a robust data layer bridging WordPress posts and pages with WooCommerce product catalogs, carts, and checkout APIs.
• Resolved variation matching bugs to ensure seamless real-time product pricing, image changes, and cart addition for variable products.
• Handled checkout configuration and integrated cash on delivery (COD) payment rules.
• Set up advanced SEO metadata, static Open Graph and Twitter sharing configurations, and integrated Google Analytics along with Meta (Facebook) Pixel for route transition tracking.

AI Agent & RAG Platform with LangChain

https://github.com/code-with-mehedi/InvizoGPT-RAG
InvizoGPT is a production-grade conversational AI platform integrating a FastAPI back end with a Next.js admin dashboard. I engineered the entire RAG pipeline using OpenAI embeddings (text-embedding-3-small) and Qdrant vector search. I built a dynamic file-importing engine supporting binary uploads (.pdf, .docx, .txt), parsing page-by-page and paragraph-by-paragraph with length-aware chunking. Additionally, I implemented messaging channels for WhatsApp (via Twilio) and Twilio Voice transcription/streaming using Deepgram. I also developed a secure role-based access control (RBAC) user management portal and a configuration dashboard that allows administrators to dynamically manage and persist API credentials directly in the environment.

InvizoCRM

https://invizocrm.com
InvizoCRM is a multi-tenant SaaS CRM platform for Shopify app owners, merchants, affiliates, and platform administrators. I designed and developed the application end-to-end, including tenant workspaces, platform-admin dashboards, onboarding flows, role-based access control, email automation, campaign management, mail logs, tenant activity tracking, affiliate programs, referral tracking, payouts, subscriptions, billing, and feature access controls. I built the back-end APIs, database schema, Prisma models, authentication, admin permissions, tenant isolation, and front-end dashboards using Next.js, React, TypeScript, Prisma, PostgreSQL, NextAuth, and Docker. I also implemented production deployment workflows with Coolify, database migrations, and operational tools for monitoring tenant usage, feature access, and platform activity.

Table Tennis Academy Management System

https://mtta.com.bd
Built a full-stack academy management system for managing table tennis operations from one centralized platform. Developed back-end and front-end modules for students, members, coaching, accounting, tournaments, ELO ratings, achievements, website content, mail system, and activity logs. The platform supports academy administration, public website content management, player performance tracking, tournament organization, and operational reporting, all built with Node.js, Express.js, Next.js, and PostgreSQL.

Invizo MCP Server

https://mcp.invizo.io
Built Invizo MCP Server, a TypeScript monorepo that connects AI tools with WordPress, WooCommerce, LearnPress, posts, pages, media, and event management. Developed an Express and Prisma back end with JWT authentication, API keys, role and scope-based policy guards, audit logging, rate limiting, and a secure WordPress relay. Also created a Next.js dashboard for login, registration, site management, API key management, user profiles, admin tools, documentation, and audit monitoring.

RAG | Chat with PDF

https://github.com/code-with-mehedi/chat-pdf-rag
A full-stack application that allows users to upload PDF documents and chat with them using AI. Built with retrieval-augmented generation (RAG) architecture.

FEATURES
• PDF Upload – Upload any PDF document.
• AI Chat – Ask questions about your uploaded documents.
• Semantic Search – Find relevant content using vector embeddings.
• Real-time Processing – Background job processing with BullMQ.
• Modern UI – Clean, responsive chat interface

RAG | YouTube Summarizer

https://github.com/code-with-mehedi/TalkTube-RAG
A YouTube retrieval-augmented generation (RAG) app: paste a YouTube URL, load the video, then ask questions, get a summary, or view the transcript. Powered by LangChain, Google embeddings, and TubeOnAI for transcription.

FEATURES
• Load any YouTube video – Paste a URL or pick a sample (TED Talk, Tech Review).
• Generate Summary – Get a concise summary of the video.
• View Transcript – See the cleaned transcript.
• Chat – Ask anything about the video; answers are based on semantic search over the transcript.

AI Chatbot

I built an AI chatbot platform using Laravel integrated with OpenAI’s API. The system handles user inputs, processes responses in real-time, and supports custom workflows. It features a clean admin dashboard for managing conversations and settings, delivering a seamless and intelligent user experience.

RedX Delivery - Shopify APP

https://apps.shopify.com/redx-delivery
RedX Delivery streamlines order fulfillment by connecting your store directly to Bangladesh's leading delivery service. With just one click, orders flow seamlessly to RedX without manual data entry, saving time and eliminating errors. Our app collects customer phone numbers during checkout, automates parcel creation, and tracks delivery status—all from your admin panel. Merchants love the efficiency gains and reduced operational overhead.

Redx for WooCommerce

https://wordpress.org/plugins/redx-for-woocommerce/
The “Redx for WooCommerce” plugin integrates Redx logistics services into your WooCommerce store, which seamlessly track your orders, manage shipment statuses, and provide tracking details to your customers directly within your WordPress admin panel.

Designed for eCommerce stores using Redx in Bangladesh, this plugin ensures efficient shipment tracking and enhanced customer satisfaction.

Lendedu

https://lendedu.com/
Joined as a Gutenberg engineer, spearheaded the development of over 20 innovative blocks, and resolved more than 200 bugs at lendedu.com. This overhaul resulted in a complete site revamp, driving an impressive 37% growth for the company.

Comment.org

https://comment.org/
Developed a custom payment gateway and tailored WooCommerce add-ons and empowered comment.org to seamlessly accept payments in dual currencies, enhancing accessibility for their global audience. Moreover, enabling bulk importation of thousands of users for membership streamlined their operations, catalyzing a remarkable 20% surge in growth. This multifaceted solution not only optimized their user experience but also significantly bolstered their organizational efficiency, positioning comment.org for sustained success in their endeavors.

Doublesdesign.com

https://www.doublesdesign.com/
Before my enhancements, Doubles Design's website was poorly designed and lacked responsiveness. Following my work, they saw a remarkable 30% increase in conversion rates, enabling them to engage their audience better.

StoreGrowth - WooCommerce Sales Booster Plugin

https://wordpress.org/plugins/storegrowth-sales-booster/
The StoreGrowth plugin is an all-in-one bundle for WooCommerce, offering more than eight modules to enhance sales funnels. It addresses the difficulty of installing multiple plugins by reducing the burden and improving website performance. Compatible with various WordPress themes, it allows full control over design and customization, including a real-time preview of changes. This plugin is designed to attract and encourage visitors to purchase, increasing sales and creating a positive impact on your business.

Animal Chiropractic Education

https://www.animalchiropracticeducation.com/
Spearheaded the development and management of a comprehensive WordPress and WooCommerce-based website, serving as the full-stack developer. My responsibilities encompassed overseeing all aspects, from resolving design issues to optimizing server performance and ensuring robust website security. Through a redesign initiative, I successfully enhanced the site's conversion rate to an impressive 50%, leveraging my expertise in user experience and conversion optimization strategies.

Table Tennis Management System

I developed a comprehensive Table Tennis Management System using Laravel that streamlines player registration, match scheduling, scoring, and ranking. The system features a robust admin dashboard for managing tournaments, real-time score updates, and user role management. It’s optimized for performance and scalability, helping the federation run smoothly and efficiently.

Senior WordPress/WooCommerce Developer

Developed a complete e-learning platform using Tutor LMS, WooCommerce, WooCommerce Subscriptions, and Stripe, implementing subscription-based access, secure payments, and automated course management, along with a custom AI chatbot and RAG system for enhanced student support and personalized learning.

Education

2012 - 2016

Bachelor of Science Degree in Computer Science

Bangladesh University of Business and Technology - Dhaka, Bangladesh

2007 - 2011

Diploma in Telecommunication Engineering

Jessore Polytechnic Institute - Jessore, Bangladesh

Skills

Libraries/APIs

WordPress API, WooCommerce API, REST APIs, Node.js, React, Playwright, API Development, jQuery, Stripe, Facebook API, SendGrid API, Twilio API, WordPress REST API

Tools

Advanced Custom Fields (ACF), Gutenberg Editor, Composer, NPM, Claude Code, Codex, GitHub, Claude, ChatGPT, NGINX, LearnPress, Mailchimp, Webpack, Figma, Google Analytics, Prisma, Git

Languages

JavaScript, CSS3, Sass, TypeScript, Python, CSS, HTML, HTML5, SQL, ECMAScript (ES6), Coolify, GraphQL

Frameworks

Divi, Next.js, Express.js, LangGraph, Tailwind CSS, Cypress, Vanilla JS, Bedrock

Paradigms

Object-oriented Programming (OOP), Responsive, Responsive Web Design (RWD), Search Engine Optimization (SEO), DevOps, Database Design

Platforms

WooCommerce, Docker, Vercel, Shopify, Amazon Web Services (AWS)

Storage

MySQL, PostgreSQL, Databases, SQLite, JSON, Redis

Other

WooCommerce Subscriptions 2, Ajax, WordPress Plugins, Plugins, Themes, Site Speed Optimization, Website Migration, WordPress Design, eCommerce, APIs, Troubleshooting, Full-stack, API Integration, Back-end, CI/CD Pipelines, Online Payments, Cold Emailing, GitHub Actions, Gemini, Cloudflare, PWA, Lovable, AI Tools, Agentic AI, Agentic RAG Systems, Large Language Models (LLMs), LangChain, Product Owner, RAG Architecture, Retrieval-augmented Generation (RAG), Artificial Intelligence (AI), AI Integration, Security, Scripting, PDF, AI Automation, AI Agents, Supabase, Multi-agent Systems, User Interface (UI), User Flows, User Experience (UX), Workflows, API Design, Architecture, Command-line Interface (CLI), Analytics, Webhooks, Full-stack Development, CRM, MVP Design, Minimum Viable Product (MVP), Emailers, IT Audits, Dashboards, RAG Systems, Software Architecture, Data Modeling, Workflow Automation, Agentic AI Systems, Agentic Workflow Design, Prompt Engineering, Data Structures, Containerization, Generative Artificial Intelligence (GenAI), Code Review, VPS, Payment APIs, Front-end, Front-end Development, Design, Learning Management Systems (LMS), FastAPI, Fintech, Finance, Plugin Development, Computer Science, NextAuth.js, Multi-tenant SaaS, Email Automation, Campaign Management, Affiliate Tracking, Paddle Subscription Billing, Authentication, Admin Dashboard Development, Accounting Module Development, Student and Member Management, ELO Rating System, Full-stack Web Development, JWT Authentication, API Key Management, OpenAI, Qdrant, Deepgram API, React 19, Meta (Facebook) Pixel, Swiper.js

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