
Harshdeep Singh
Verified Expert in Engineering
Full-stack Developer
Vancouver, BC, Canada
Toptal member since May 10, 2022
Harshdeep, a seasoned full-stack developer with five years of MERN stack experience, excels in development phases, optimizing performance, scalability, and security. He is recognized for problem-solving, delivering high-quality web solutions, and driving business success through exceptional user experiences. He efficiently manages projects with effective communication and collaboration skills, exceeding client expectations. Full portfolio and articles at https://theharshdeepsingh.com
Portfolio
Experience
- JavaScript - 5 years
- React - 5 years
- Node.js - 5 years
- MongoDB - 4 years
- Express.js - 3 years
- CSS - 3 years
- React Native - 1 year
- TypeScript - 1 year
Preferred Environment
MacOS, Linux, WebStorm, Visual Studio Code (VS Code), Front-end, GitHub, NoSQL, Git, JSON REST APIs, Mobile Development
The most amazing...
...product I've worked on is the eCommerce website for Tokopedia, the top eCommerce organization in Indonesia.
Work Experience
Full-stack Developer
The Acquisition Group
- Contributed to the design and production deployment of a full-stack marketplace platform used by internal sales teams, supporting concurrent user activity and real-time data interactions across client–seller workflows.
- Engineered scalable React-based front-end modules and reusable component architecture, improving maintainability and reducing feature delivery time across iterative releases.
- Designed and optimized RESTful APIs using Node.js and Express, improving data retrieval efficiency and reducing dashboard load time by 20% through query tuning and API payload minimization.
- Implemented CI/CD workflows to streamline build validation and controlled production releases, ensuring stable deployments and reducing regression risks.
- Maintained website security measures to protect against cyber threats.
- Integrated logging and runtime error monitoring practices to proactively detect and resolve production issues, improving overall application reliability.
- Optimized dashboard performance, reducing load times by 20% and enhancing the overall user experience.
- Supported secure JWT-based authentication flows and role-based access control (RBAC), strengthening API security and protecting sensitive operational data.
Full-stack Developer
Independence Financial Network, LLC
- Engineered a fully responsive HTML email and landing page system with dynamic CSV-based personalization, boosting campaign engagement for a US financial services client.
- Automated end-to-end lead flow using Zapier, integrating Mailjet, custom React landing pages, and Shape CRM to streamline outreach and data capture.
- Implemented Sanity Studio as a CMS to manage marketing content dynamically, enabling non-technical team members to update emails and landing pages efficiently.
Full-stack Developer
Creative Strategies & Communications, Inc.
- Converted high-fidelity Sketch designs into pixel-perfect, fully responsive React web pages, ensuring cross-browser compatibility and optimal performance across various screen sizes.
- Integrated RESTful APIs and optimized front-end data handling, implementing efficient state management (using React Context and Redux) to enhance application responsiveness and reduce unnecessary re-renders.
- Developed and maintained reusable, modular React components with optimized styling (CSS-in-JS and Styled Components), improving scalability and reducing redundant code.
- Collaborated closely with back-end developers to debug API integration issues, optimize data fetching strategies, and enhance overall application performance, ensuring seamless user interactions.
Front-end JavaScript Developer
Get2it, Inc.
- Converted high-fidelity Sketch designs into pixel-perfect, fully responsive React web pages, ensuring cross-browser compatibility and optimal performance across various screen sizes.
- Integrated RESTful APIs and optimized front-end data handling, implementing efficient state management (using React Context and Redux) to enhance application responsiveness and reduce unnecessary re-renders.
- Developed and maintained reusable, modular React components with optimized styling (CSS-in-JS and Styled Components), improving scalability and reducing redundant code.
- Collaborated closely with back-end developers to debug API integration issues, optimize data fetching strategies, and enhance overall application performance, ensuring seamless user interactions.
Full-stack Engineer
Grown Unknown, LLC
- Integrated OpenAI API for user content creation, to enhance astrology content creation within the platform, contributing to a more engaging user experience.
- Led the development of eCommerce solutions for clients, incorporating CRM management through Shopify to streamline business operations and enhance customer interactions.
- Orchestrated email campaign automation using Klaviyo, resulting in improved communication strategies for both new and existing users.
- Engineered intricate multi-layered relationships among platform users, implementing a Family-like relations system to foster stronger user connections.
- Spearheaded the end-to-end development of a comprehensive platform, drawing inspiration from Figma for design and utilizing Express and MongoDB on the back end for robust business logic implementation and efficient database management.
React Developer
WorkRamp, Inc.
- Enhanced product accessibility by implementing Accessible Rich Internet Applications (ARIA) rules, ensuring compliance with accessibility standards, and improving user experience.
- Significantly improved the accessibility score of the product, elevating it from approximately 30% to an impressive 95%, demonstrating a commitment to inclusivity and user-friendly design.
- Optimized some systems in the product to be more organized and be more reusable all across.
- Implemented optimization strategies for various systems within the product, resulting in increased organization and reusability across the project, streamlining development processes and promoting efficiency.
Senior Full-stack Developer | React and Node.js
Aqueous Asset Inc.
- Pioneered the development of a novel system for creating offering memorandums tailored specifically for US properties, introducing a comprehensive and efficient solution to address specific business needs.
- Expanded the functionality of the existing system through strategic abstraction, enhancing its capabilities and ensuring scalability to meet evolving business requirements.
- Spearheaded a code revamp initiative, significantly improving code reusability and readability, resulting in a more maintainable and streamlined codebase for enhanced collaboration and future development efforts.
Software Engineer
Tokopedia
- Charged with maintaining the front-end design part in React for multiple eCommerce platform services.
- Achieved a 30% increase in test case coverage, 50% in statement coverage, and 40% in branch coverage for existing components, enhancing application reliability.
- Directed the hiring process, conducting 30+ interviews to attract high-caliber professionals and uphold organizational standards.
- Mentored new team members, facilitating a smooth transition from academia to industry and contributing to their professional development.
Software Engineer
TO THE NEW Pvt. Ltd.
- Adhered to best practices and coding standards to develop high-quality software solutions using programming languages.
- Designed, developed, and deployed software to meet business needs.
- Outlined specifications and performance requirements, working with the quality assurance team to thoroughly test all variables.
- Built responsive and user-friendly interfaces, integrated APIs, and implemented server-side functionalities to deliver robust web applications.
- Mentored junior developers on query tuning and best practices to maximize database performance.
Experience
Career Canvas
Users craft tailored resumes with ease, choose from various templates, and access real-time job listings. The platform's MERN stack foundation ensures scalability and reliability, while future plans aim to enhance features and expand resources for interview prep and career guidance. Career Canvas empowers users to navigate their professional journeys effectively, positioning it as an indispensable tool for career success.
Unconventional Player
This was developed on the MERN stack using Cloudinary as a shared cloud space to store audio files.
USE CASES
• Musicians who are learning to play instruments can benefit from this using a footpad as a mouse.
• With some modifications, it could be useful for a better accessibility music player
Suite of Apps for a Photography Gallery Webpage
I created a React webpage to display all the images stored in Cloudinary using Express.js in the back end. To complement the webpage, I built a React Native app for the administrative side of the solution. Using the app, I uploaded media to Cloudinary via the Express.js back end, enabling the uploaded media to be automatically displayed on all social media accounts and my client webpage.
StockFlow AI - Automated Media Submission and Upload Pipeline
https://github.com/harshdeepsingh13/stockflow-ai• Designed a modular, platform-agnostic service architecture (factory and abstraction layers) enabling seamless extension to multiple marketplaces (Shutterstock, Getty, and Adobe Stock), significantly improving scalability and long-term maintainability.
• Integrated local LLM and vision models (Ollama and LLaMA) to generate high-quality titles, descriptions, and tags, reducing external API dependency and optimizing operational cost while maintaining deterministic, production-ready outputs.
• Built resilient browser automation workflows using Playwright CDP, including state detection, anti-bot timing strategies, retry logic, and failure handling to ensure reliable execution against dynamic third-party platforms.
• Engineered a fault-tolerant pipeline with validation, retry mechanisms, and structured logging (JSON and CSV), enabling traceability, bulk operations, and consistent compliance with platform-specific submission constraints.
Education
Post-Baccalaureate Diploma in Data Analytics
Douglas College - New Westminster, BC, Canada
Bachelor of Technology Degree in Computer Science
Guru Gobind Singh Indraprastha University - Delhi, India
Skills
Libraries/APIs
React, Node.js, REST APIs, React Router, React Redux, D3.js, Puppeteer, API Development, Socket.IO, Highcharts, AG Grid, Stripe, Auth, Mapbox API, Vue, Chart.js, OpenAI API, Claude API, Playwright
Tools
Figma, GitHub, Git, Auth0, NPM, Webpack, Google Analytics, Figma to HTML, SendGrid, Zapier, Claude, Claude Code, Vitest, Microsoft Power BI, ChatGPT, Sketch, Cron, Mailchimp
Languages
JavaScript, CSS, HTML, Sass, ECMAScript (ES6), SQL, TypeScript, HTML5, SCSS, CSS3, GraphQL, C#, Python
Frameworks
Express.js, JSON Web Tokens (JWT), Bootstrap, OAuth 2, WebApp, MUI CSS, React Native, Redux, Material UI, Next.js, Jest, Tailwind CSS
Paradigms
Agile, UX Design, Component-based Development, Code Refactoring, Refactoring, Agile Software Development, Responsive Web Design (RWD), UI Design, REST, DevOps, Microfrontends, Real-time Systems, Unit Testing, Testing, Test-driven Development (TDD), E2E Testing, Web UI Design, Mobile Development
Platforms
Web, Amazon Web Services (AWS), Vercel, Heroku, Amazon EC2, Shopify, Android, iOS, AWS IoT, Docker, AWS Lambda, Sanity Studio, Twilio, Azure, Ollama
Storage
MongoDB, JSON, JSON/XML Schemas, MySQL, NoSQL, Redis, Amazon S3 (AWS S3), Data Integration, PostgreSQL
Industry Expertise
Web Design, Social Media
Other
Web Development, APIs, Back-end Development, Front-end, Front-end Development, Full-stack Development, Back-end, Web Accessibility, Design, Websites, Mobile First, PWA, OAuth, UI Development, CSV, JSON REST APIs, Technical Hiring, User Interface (UI), User Experience (UX), MERN Stack, Full-stack, Animation, Startups, Third-party APIs, API Integration, Styled-components, Google Analytics 4 (GA4), CI/CD Pipelines, Google+ Authentication, Front-end Architecture, Leadership, Mobile Video, OpenAI, Data Visualization, ChatGPT API, Dashboards, Squarespace, Progressive Web Applications (PWAs), Browser Automation, Algorithms, Code Review, Team Mentoring, Landing Pages, WebSockets, Email Templates, HTML Email, Figma to React, Large Language Models (LLMs), Data Modeling, AI Tools, Legacy Code, Technical Architecture, Security, Payments, AI-generated Code, JWT Authentication, Streaming Data, Event-driven Systems, Vibe Coding, Software Architecture, Integration Testing, Performance Optimization, Cloudinary, Software Deployment, PDF, Minimum Viable Product (MVP), API Documentation, eCommerce, Team Leadership, Webhooks, Learning Management Systems (LMS), Web App UX, OpenAI GPT-4 API, Data Scraping, Software Development, RESTful Web Services, Web Scraping, Artificial Intelligence (AI), Chakra UI, Email Marketing Automation, Customer Relationship Management (CRM), Mailjet, Content Management Systems (CMS), Cursor AI, AI Integration, Document Parsing, Mobile App Development, Mobile Apps, Payment Gateways, Payment APIs, Marketplaces, Source Code Review, Vision models, Prompt Engineering, LangChain, AI Automation
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