Kousik Chandra, Developer in Kolkata, West Bengal, India
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Kousik Chandra

Software Development Developer

Kolkata, West Bengal, India

Toptal member since May 27, 2026

Bio

Full-stack Web and Mobile Developer with 5+ years of experience building scalable applications across web and mobile platforms. Skilled in MERN and PERN stacks, Python with Django, React Native, and Android. Experienced in developing end-to-end solutions, from UI to APIs and databases, with a strong focus on performance, clean code, and real-world problem-solving.

Portfolio

Freelancer
JavaScript, Node.js, React, Python 3, React Native, WordPress...
Online Freelance Agency
JavaScript, React, Android, Windows

Experience

  • Node.js - 5 years
  • Python 3 - 5 years
  • Software Development - 5 years
  • React Native - 5 years
  • React - 5 years
  • WordPress - 5 years
  • Web Development - 5 years
  • Full-stack - 5 years

Preferred Environment

Windows, Android, Web Development, Website Optimization, CSS Animations, Coding, Software Development, C++

The most amazing...

...thing: I have helped businesses streamline their entire business processes, reducing their workload by 80% .

Work Experience

Full-stack Web and Mobile Developer

2020 - PRESENT
Freelancer
  • Created a clinic management solution for a clinic, which helped them to streamline their business processes.
  • Developed an inventory management application for a boutique.
  • Developed an offline field management mobile application for a brand, which helped track their offline counters.
  • Built a billing POS application for a retail client.
  • Built an ERP solution for a retail client, which helped them to streamline their entire business processes.
  • Created a CRM application for a real estate client, which helped them track their leads.
  • Developed a help desk application for a logistics client, which helped them streamline their client queries.
  • Developed a chatbot application for a clinic that helped them answer client queries.
Technologies: JavaScript, Node.js, React, Python 3, React Native, WordPress, Search Engine Optimization (SEO), Web Development, Website Optimization, CSS Animations, Coding, HTML5, Tailwind CSS, Elementor Pro, Software Development, Web App Deployment, PostgreSQL, RESTFul APIs, Machine Learning, Express.js, Windows, Amazon Web Services (AWS), Query Optimization, SQL Performance, Back-end, Full-stack, Large Language Models (LLMs), AI Model Training, Code Review, C++, Python, TypeScript, AI Modeling, API Integration, REST APIs, Technical Design, Debugging, Shopify, eCommerce, Third-party Integration, Shopify Customizations, Shopify Plus, Product Management, Responsive Web Design (RWD), Shopify Liquid, Shopify Theme, Web Design, API Architecture, API Design, API Testing, JSON, MongoDB, OpenID Connect (OIDC)

Full-stack Web and Mobile Developer

2018 - PRESENT
Online Freelance Agency
  • Developed a mobile application for an offline brand to track the efficiency of employees.
  • Built a content management system (CMS) for a hair salon client.
  • Built an electronic health record (EHR) system for a clinic to help them track their patients.
Technologies: JavaScript, React, Android, Windows

Experience

Clinic Management Solution

Clinic management software designed for modern doctors and clinics to streamline operations, reduce manual work, and improve patient care. It combines a professional marketing website with powerful features like appointment scheduling, real-time availability updates, patient and prescription management, and automated follow-up reminders.

The system provides a smart dashboard where doctors can track appointments, cancellations, new patients, online vs. offline bookings, and analyze trends across 1, 3, 6, and 12 months. It also offers insights into patient demographics, symptoms, and most prescribed medicines, helping in data-driven decision-making. Built-in tools allow clinics to publish SEO-friendly blogs, services, and testimonials, along with instant practice notifications.

Built using the PERN stack (PostgreSQL, Express.js, React, Node.js), the platform is scalable, secure, and optimized for performance, enabling clinics to grow efficiently while delivering a better patient experience.

Halth and Wellness Supplement Store

Developed a fully responsive Shopify eCommerce store for a health and wellness brand specializing in daily nutritional greens supplements. The website was designed to provide a seamless shopping experience while effectively communicating the product's health benefits, ingredients, and subscription options.

Key features included:
Custom Shopify theme customization
Product catalog management and subscription-based purchasing
Mobile-responsive design for all devices
Optimized product pages with conversion-focused layouts
Secure checkout and payment integration
Customer reviews and trust-building elements
Performance and speed optimization
SEO-friendly structure to improve organic visibility

The project focused on creating a modern, high-converting online store that helps customers easily discover, understand, and purchase premium nutritional supplements while supporting the brand's long-term growth and customer retention goals.

WordPress Website for A Surgical Gastroenterology Specialist

Developed a professional WordPress website for a surgical gastroenterology, GI oncology, advanced laparoscopy, and robotic surgery specialist. The website was designed to establish credibility, educate patients, and streamline the appointment booking process while maintaining a modern and professional online presence.

Key features included:
• Custom WordPress design and development
• Mobile-responsive layout optimized for all devices
• Service pages showcasing treatments, procedures, and medical expertise
• Patient education content and blog integration
• Appointment booking and contact inquiry functionality
• Testimonial and trust-building sections
• SEO-friendly website architecture for improved search visibility
• Performance optimization for faster page load times

The project focused on creating a patient-centric digital experience that improves online visibility, builds trust with prospective patients, and helps generate appointment inquiries through organic search and digital marketing efforts.

Education

2016 - 2018

Master's Degree in Computer Science

Institute of Science Banaras Hindu University - Varanasi

Skills

Libraries/APIs

Node.js, React, REST APIs, Shopify API

Tools

Shopify Plus

Languages

JavaScript, Python 3, HTML5, C++, Python, TypeScript, Shopify Liquid

Frameworks

React Native, Express.js, Tailwind CSS

Paradigms

Search Engine Optimization (SEO), API Architecture, Responsive Web Design (RWD)

Platforms

Android, WordPress, Windows, Amazon Web Services (AWS), Shopify

Storage

PostgreSQL, JSON, MongoDB, SQL Performance

Industry Expertise

Web Design

Other

Software Development, Web App Deployment, RESTFul APIs, Web Development, Website Optimization, CSS Animations, Coding, Back-end, Full-stack, API Integration, Technical Design, Shopify Customizations, API Design, API Testing, OpenID Connect (OIDC), Machine Learning, Elementor Pro, Query Optimization, Large Language Models (LLMs), AI Model Training, Code Review, AI Modeling, Debugging, eCommerce, Third-party Integration, Shopify SEO, Product Management, Shopify Theme

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