Hi there! 👋 I'm a Senior Ruby on Rails and Full Stack Developer with over 10 years of experience building high-quality, scalable, and performance driven web applications. I specialise in turning complex ideas into robust digital solutions, combining backend expertise, modern frontend technologies, and cloud infrastructure to deliver end-to-end systems that meet your business goals. I have successfully led and delivered projects using Ruby on Rails, Angular, ReactJS, Node.js, and other cutting-edge technologies, backed by strong database expertise in PostgreSQL, MySQL, MongoDB, and Cassandra. I also integrate AI-driven features, modern frontend frameworks like Next.js, and microservices architecture for scalable and maintainable platforms. My approach is client-focused: I take the time to understand your vision, design tailored solutions, and ensure smooth implementation from project planning to deployment and maintenance. I value clear communication, timely delivery, and long-term collaboration. Skills & Expertise: - [Backend]: Ruby on Rails, Node.js, API development, AI/ML integrations (OpenAI, Anthropic, Langchain.rb) - [Frontend]: Stimulus, Angular, ReactJS, Next.js, TypeScript, JavaScript, Bootstrap - [Databases]: PostgreSQL, MySQL, MongoDB, Cassandra - [DevOps & Cloud]: AWS, Heroku, Docker, Nginx, Apache, CI/CD, Capistrano - [Code Management & Testing]: Git, GitHub, Bitbucket, GitLab, Subversion, RSpec, TDD - [Markup & Styling]: HTML, Haml, Slim, CSS, SCSS - [Collaboration & Leadership]: Team management, agile workflows, code reviews, mentoring I help clients launch new platforms, modernize legacy systems, and integrate advanced features with a focus on scalability, security, and performance. Whether you need a custom web application, an upgrade to an existing system, or ongoing technical support, I bring both expertise and a collaborative approach to your project. Let's discuss your project and turn your ideas into a solution that drives real value.

I am Sr. Ruby on Rails developer. I have more than 9 years of experience as a full stack developer, a tech enthusiast, and expertise in Finance, E-commerce, Education, Food and AI. We have started working with AI as well and would like to assist client with our knowledge and experience. I help clients to build a web application from scratch to deployment and maintenance. I closely work with clients to understand their requirements and developed application that meets their expectations within time limits.

🚀 𝐓𝐨𝐩 𝐑𝐚𝐭𝐞𝐝 | ✅ 𝐒𝐡𝐨𝐩𝐢𝐟𝐲 𝐄𝐱𝐩𝐞𝐫𝐭 | ✅ 𝐑𝐮𝐛𝐲 𝐨𝐧 𝐑𝐚𝐢𝐥𝐬 𝐄𝐱𝐩𝐞𝐫𝐭 | 🕒 𝐀𝐯𝐚𝐢𝐥𝐚𝐛𝐥𝐞 𝐈𝐦𝐦𝐞𝐝𝐢𝐚𝐭𝐞𝐥𝐲 I’m an experienced Full-Stack Developer with 7 years of experience building scalable, high-performance web applications and conversion-focused e-commerce stores. I specialise in Ruby on Rails for robust back-end systems and Shopify for crafting powerful, revenue-driven online stores. Whether you need a custom web platform or a high-converting Shopify store, I bring a balance of clean code, modern design, and business-focused strategy to every project. Throughout my career, I’ve delivered a diverse range of solutions from scalable Ruby on Rails applications like healthcare platforms, CRMs, e-learning systems, and data dashboards to high-performing Shopify e-commerce stores. 💼 Services I Offer: 👉 𝐒𝐡𝐨𝐩𝐢𝐟𝐲 & 𝐒𝐡𝐨𝐩𝐢𝐟𝐲 𝐏𝐥𝐮𝐬 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 🔹Custom Shopify theme development (Figma → pixel-perfect Shopify) 🔹Shopify Plus builds with advanced customization & scalability 🔹Conversion-focused UX/UI improvements 🔹Store setup, redesign, and feature enhancements 👉 𝐑𝐮𝐛𝐲 𝐨𝐧 𝐑𝐚𝐢𝐥𝐬 & 𝐂𝐮𝐬𝐭𝐨𝐦 𝐖𝐞𝐛 𝐀𝐩𝐩𝐥𝐢𝐜𝐚𝐭𝐢𝐨𝐧𝐬 🔹Scalable SaaS, CRM, dashboards, and custom platforms 🔹API development & third-party integrations 🔹Secure, maintainable, and high-performance backend systems 🔹Full-cycle development from MVP to enterprise-grade apps 👉 𝐌𝐢𝐠𝐫𝐚𝐭𝐢𝐨𝐧𝐬 & 𝐑𝐞𝐩𝐥𝐚𝐭𝐟𝐨𝐫𝐦𝐢𝐧𝐠 🔹Magento, WooCommerce, BigCommerce, OpenCart → Shopify or Rails 🔹Secure migration of products, customers, orders, and SEO data 🔹Rebuilding legacy systems into modern, scalable architectures 🔹Complex product logic, variants, and custom workflows 👉 𝐀𝐝𝐯𝐚𝐧𝐜𝐞𝐝 𝐂𝐮𝐬𝐭𝐨𝐦𝐢𝐳𝐚𝐭𝐢𝐨𝐧 & 𝐈𝐧𝐭𝐞𝐠𝐫𝐚𝐭𝐢𝐨𝐧𝐬 🔹Shopify: custom sections, metafields, and checkout logic (Plus) 🔹Rails: custom business logic, background jobs, API integrations 🔹ERP, CRM, payment gateways, and shipping integrations 🔹Automation workflows to streamline operations 🛒 Industries and Solutions Delivered: ➤ Fashion & Apparel ➤ Health, Wellness & Supplements ➤ Home, Living & Lifestyle ➤ B2B, Wholesale & Manufacturing ➤ SaaS Platforms, Marketplaces & Data Dashboards 🔧 Tools & Technologies: 🛒𝐄-𝐜𝐨𝐦𝐦𝐞𝐫𝐜𝐞 & 𝐒𝐡𝐨𝐩𝐢𝐟𝐲 - Shopify, Shopify Plus, Liquid, JavaScript, HTML/CSS - Klaviyo, GA4, Stripe, PayPal, Razorpay ⚙️ 𝐅𝐮𝐥𝐥-𝐒𝐭𝐚𝐜𝐤 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 - Ruby on Rails, Node.js, Express.js - React.js, Next.js, Redux, Vue.js - JavaScript (ES6+), TypeScript 🗄️ 𝐃𝐚𝐭𝐚𝐛𝐚𝐬𝐞𝐬 & 𝐀𝐏𝐈𝐬 - MongoDB, PostgreSQL, MySQL - REST APIs, GraphQL, Firebase 🎨𝐅𝐫𝐨𝐧𝐭𝐞𝐧𝐝 & 𝐔𝐈 - Tailwind CSS, SCSS, SASS, Bootstrap, GSAP - Figma (pixel-perfect implementation) ☁️ 𝐂𝐥𝐨𝐮𝐝 & 𝐃𝐞𝐯𝐎𝐩𝐬 - AWS, Azure, GCP, RunPod 🤖𝐀𝐈 & 𝐀𝐮𝐭𝐨𝐦𝐚𝐭𝐢𝐨𝐧 - ChatGPT integrations, AI-powered workflows 💡 What Sets Me Apart: ✔ Strong blend of Shopify e-commerce + Ruby on Rails engineering ✔ Focus on business results, not just development ✔ Clean, scalable, and future-proof code ✔ Proven ability to handle complex, high-growth projects 🚨𝐈𝐟 𝐲𝐨𝐮'𝐫𝐞 𝐥𝐨𝐨𝐤𝐢𝐧𝐠 𝐟𝐨𝐫 𝐚 𝐟𝐮𝐥𝐥-𝐬𝐭𝐚𝐜𝐤 𝐞𝐱𝐩𝐞𝐫𝐭 𝐰𝐡𝐨 𝐜𝐚𝐧 𝐛𝐮𝐢𝐥𝐝 𝐜𝐨𝐦𝐩𝐥𝐞𝐱 𝐚𝐩𝐩𝐬, 𝐬𝐜𝐚𝐥𝐞 𝐢𝐧𝐟𝐫𝐚𝐬𝐭𝐫𝐮𝐜𝐭𝐮𝐫𝐞, 𝐚𝐧𝐝 𝐝𝐞𝐥𝐢𝐯𝐞𝐫 𝐩𝐨𝐥𝐢𝐬𝐡𝐞𝐝 𝐔𝐈𝐬, 𝐈'𝐦 𝐡𝐞𝐫𝐞 𝐭𝐨 𝐛𝐫𝐢𝐧𝐠 𝐲𝐨𝐮𝐫 𝐯𝐢𝐬𝐢𝐨𝐧 𝐭𝐨 𝐥𝐢𝐟𝐞. 𝐖𝐡𝐞𝐭𝐡𝐞𝐫 𝐢𝐭'𝐬 𝐒𝐡𝐨𝐩𝐢𝐟𝐲, 𝐑𝐚𝐢𝐥𝐬, 𝐨𝐫 𝐑𝐞𝐚𝐜𝐭, 𝐈’𝐥𝐥 𝐡𝐞𝐥𝐩 𝐲𝐨𝐮 𝐬𝐡𝐢𝐩 𝐟𝐚𝐬𝐭 𝐚𝐧𝐝 𝐬𝐦𝐚𝐫𝐭!

✔︎ Hi, I'm a Full-Stack Developer with 7+ years of experience in 🔸 Ruby on Rails, 🔸 Front-End Development, 🔸 Sharetribe, and 🔸 DevOps. Hi, I’m a Full-Stack Developer with 5+ years of experience building scalable web apps, SaaS platforms, and marketplaces. I now help businesses integrate AI into their products to automate workflows, enhance user experience, and unlock new revenue streams. 💡 What I Do Best 🧠 **AI-Powered Development (NEW AGE FOCUS)** ✔︎ Integrate AI into web apps (OpenAI, AI APIs, automation tools) ✔︎ Build AI-driven features: recommendations, chatbots, content generation ✔︎ AI-based workflows (analysis, personalization, smart search) ✔︎ Prompt engineering & optimization for real-world applications ✔︎ AI + SaaS product development (MVP to scale) 💎 **Ruby on Rails (Backend Expertise)** ✔︎ Scalable Rails apps (Monolith & API-first architecture) ✔︎ RESTful APIs, background jobs (Sidekiq, Delayed Job) ✔︎ Authentication (Devise, JWT), authorization (Pundit) ✔︎ Payment integrations (Stripe, PayPal, subscriptions, invoicing) ✔︎ Performance optimization, caching, and DB tuning ✔︎ TDD with RSpec & Capybara 🏪 **Marketplace Specialist (Sharetribe Expert)** ✔︎ Sharetribe Go & Flex customization ✔︎ Custom marketplace features (booking, availability, pricing logic) ✔︎ Payment gateway integrations (Stripe, Razorpay, etc.) ✔︎ Migration, scaling & advanced custom workflows 🎨 **Front-End Development** ✔︎ React.js, JavaScript (ES6+), jQuery ✔︎ HTML5, CSS3, SCSS, Bootstrap ✔︎ Pixel-perfect UI from Figma/PSD ✔︎ Responsive, fast, and accessible design ✔︎ Performance optimization (Core Web Vitals, Lighthouse) ⚙️ **DevOps & Deployment** ✔︎ AWS (EC2, S3, RDS), DigitalOcean, Heroku ✔︎ CI/CD pipelines, Docker (basic to intermediate) ✔︎ Nginx, SSL, server optimization ✔︎ Monitoring, scaling, and maintenance 🔥 Why Clients Choose Me ✔︎ AI-ready development approach (future-proof solutions) ✔︎ Strong product thinking (not just coding) ✔︎ Clean, scalable, and maintainable code ✔︎ Fast communication & reliable delivery ✔︎ Long-term support & collaboration mindset 💬 Let’s Work Together Whether you're: • Building an AI-powered SaaS 🚀 • Launching a marketplace 🏪 • Automating business workflows 🤖 • Scaling an existing Rails app ⚡ I can help you turn your idea into a powerful, production-ready product. 📩 Send me a message — happy to discuss your project!

Currently, I am an independent software engineer. My Cat Feeding Tracker app demonstrates my ability to build user-facing features and implement RESTful integrations. I’m skilled in Ruby on Rails, Ruby, JavaScript, TypeScript, Node.js, Heroku/Render, TailwindCSS. Before transitioning into software development, I worked as a Global Process Engineer, where I led cross-functional raw material evaluation projects across distributed teams. In this role, I practiced product thinking—always focused on improving existing product performance and solving issues. I prioritized team success and long-term sustainability over individual achievements, consistently leveraging technology for problem-solving and data analysis.

I’m Bablu Kumar, a senior full-stack web developer with 7+ years of experience building scalable platforms, complex systems, and marketplace products that handle real users and real payments. I work with founders who need more than basic development — they need systems that are reliable, extensible, and built for real-world use. My core expertise includes React, Node.js, Ruby on Rails, Laravel, Stripe with advanced payment flows and webhooks, AWS S3, and AI integrations using ChatGPT and OpenAI APIs. I focus on clean architecture, strong coding standards, and maintainable systems so products can grow without constant rewrites or technical debt. I build MVPs that launch fast but are engineered for long-term scale. I’m also a verified Sharetribe expert, bringing deep marketplace experience when required — from payments and workflows to edge cases and platform limitations.

Building state-of-the-art, user-friendly websites is my passion. I take pride in crafting high-performance, intuitive web applications that meet modern industry standards. I am confident that my skills and experience make me an excellent choice for your projects. I stay ahead of the curve by continuously learning new technologies and keeping up with the latest industry trends. This proactive approach allows me to deliver exceptional solutions that not only meet but exceed client expectations. Let’s build something great together!

I'm a well experience Full Stack developer having 12+ years of experience in Web & API Development. Working on projects I always care about code quality and general solution usability. It's important for me to build long term relationships with clients, so I'm primarily looking for long term projects. I'm flexible with my working hours and would be happy to work closely with your team. I'm comfortable with speaking, reading and writing English. My Skills are: - Ruby on Rails - React JS - Angular JS, 2, 4, 5, 6 - Front end (JavaScript, jQuery, Ajax, Sass, Haml , Twitter bootstrap, etc) - Database used : Postgres, MySQL - have done deployments on server : AWS, ec2, Digital Ocean, Heroku Looking forward to hearing from you.

⭐⭐⭐⭐⭐ "Great experience!!" Goal-oriented Fractional CTO with a demonstrated history in building SaaS products.

I help product teams build, stabilize, and improve Ruby on Rails applications. I have 16 years of Rails experience and 20 years building software products across SaaS, marketplaces, healthcare, payments, real estate, booking systems, and internal tools. I am most useful when a project needs senior ownership: someone who can join an existing codebase, understand the product, make practical technical decisions, and ship production work without heavy supervision. What I can help with: - New Rails features and full product workflows - Rails API design, integrations, and backend architecture - PostgreSQL, Redis, Sidekiq, Hotwire/Turbo, Stimulus, React, React Native - AWS-backed infrastructure and integrations, including Amazon Bedrock where it fits the product - Stripe payments, marketplace flows, booking systems, and admin tools - Performance work, production debugging, and legacy code cleanup - Role-based permissions and internal operations workflows - AI/RAG features inside existing products: embeddings, pgvector, semantic search, AWS Bedrock, Claude, OpenAI, and LLM workflows Recent work: - Led engineering for a Rails real estate marketplace, covering architecture, delivery, and production decisions. - Built workflow automation and granular role-based permissions for internal operations. - Scaled a high-traffic Ruby service from 50k to 150k requests/minute ahead of Black Friday by tuning ActiveRecord pooling and rewriting hot-path queries. - Built booking and mobile product flows across a Rails API, Redis-backed scheduling, React Native, and Stripe. - Built natural-language search over HTA documents using embeddings, pgvector, structured filters, and a RAG service. I care about simple architecture, clear communication, small deliverables, reliable deployments, and code that is easy to maintain after the first release. If you need a senior Rails engineer who can own a feature end-to-end, stabilize a production app, or help a small team move faster, I am a good fit.