Nikhil is available for hire
Hire NikhilNikhil Garg
Verified Expertย in Engineering
Full-stack Development Developer
Sahibzada Ajit Singh Nagar, Chandigarh, India
Toptal member since July 18, 2025
Bio
Nikhil is a product minded ๐ ๐๐ฅ๐ก, ๐ฅ๐ฒ๐ฎ๐ฐ๐ ๐ก๐ฎ๐๐ถ๐๐ฒ and ๐ฃ๐๐ฃ developer with 13+ years experience, currently focused on building ๐ฆ๐ฎ๐ฎ๐ฆ ๐๐ผ๐น๐๐๐ถ๐ผ๐ป๐ end to end. He took projects from ๐ฑ๐ถ๐๐ฐ๐ผ๐๐ฒ๐ฟ๐ โ ๐ฟ๐ผ๐ฎ๐ฑ๐บ๐ฎ๐ฝ๐ โ ๐ ๐ฉ๐ฃ and scale them on AWS and GCP. He delivered ๐บ๐ฒ๐ฎ๐๐๐ฟ๐ฎ๐ฏ๐น๐ฒ ๐ฟ๐ฒ๐๐๐น๐๐ like 42 percent reduction in claim handling time and 99.95 percent uptime. Strong with ๐ฎ๐ป๐ฎ๐น๐๐๐ถ๐ฐ๐, ๐ฝ๐ฎ๐๐บ๐ฒ๐ป๐๐, ๐๐ฅ๐ , and ๐๐ฃ๐ ๐ถ๐ป๐๐ฒ๐ด๐ฟ๐ฎ๐๐ถ๐ผ๐ป๐.
Portfolio
Aureus Pay LLC
Back-end, Integration, Fintech, Payments, Node.js, TypeScript, Spring Boot...
HEXATRASH LTD
JavaScript, TypeScript, SQA, Node.js, CSS, React, Git, MySQL...
Mathpr
Front-end, User Experience (UX), Web Development, Back-end, Web Scraping...
Experience
- Full-stack Development - 12 years
- REST APIs - 8 years
- SaaS - 8 years
- Express.js - 5 years
- Node.js - 5 years
- React Native - 5 years
- OpenAI API - 5 years
- Next.js - 3 years
Preferred Environment
MongoDB, Node.js, Express.js, PHP, WordPress, React, Next.js, OpenAI API, REST APIs, React Native
The most amazing...
...thing I've built from the ground up is CodeWarranty, a SaaS platform, empowering manufacturers to automate warranty management and scale with confidence.
Work Experience
Back-end Engineer
2026 - 2026
Aureus Pay LLC
- Architected and led the end-to-end delivery of SwapyGo, a B2B fintech infrastructure platform enabling USDC-to-Vietnamese Dong (VND) cross-border payment rails for business clients, including exchanges, wallets, and card issuers.
- Designed a multi-partner, multi-tenant payment orchestration system from scratch using TypeScript, Fastify, Prisma, PostgreSQL, Redis, and BullMQโbuilt adapter-first so new markets and payment processors can be onboarded without core changes.
- Owned all money-critical and auth-critical code, including the full payment state machine, row-level locking, double-entry ledger service, FX rate snapshotting, and RSA-signed API authentication with 9Pay.
- Integrated 9Pay's disbursement API (API v4.7) for real-time USDC/VND FX rate fetching, QR-based merchant settlement, callback handling, and prefunding orchestration across Ethereum, Arbitrum, and Polygon networks.
- Established interface-first engineering discipline across a 3-person teamโall adapter contracts, API schemas, and state transition interfaces were locked before implementation began, eliminating integration rework.
- Delivered production hardening sprint covering structured error handling, payment audit trail, ledger reconciliation jobs, float monitoring, stuck payment recovery, and credential securityโbringing the system to pre-launch readiness.
Technologies: Back-end, Integration, Fintech, Payments, Node.js, TypeScript, Spring Boot, FastAPI, NestJS, PostgreSQL, ACID, Row-level Security (RLS), Efficient Data Serialization, Open Banking APIs, OAuth 2, JSON Web Tokens (JWT), Role-based Access Control (RBAC), AWS Secrets Manager, HashiCorp Vault, Winston, Grafana, Prometheus, Redis, Amazon ElastiCache, Amazon RDS, CI/CD Pipelines, Jest, Ledgers, Express.js, MySQL, BullMQ, Kafka Connect, RabbitMQ, GCP DevOps, Docker, DevOps, Django, Webhooks, APIs, REST, Sidekiq, Celery, Vault, Python, Payment Gateways, Architecture, React, Claude Code, Fractional CTO
Senior Full-Stack Engineer (PWA)
2025 - 2026
HEXATRASH LTD
- Set up an AWS EC2 instance (t3.large, Ubuntu) to host the entire back-end application.
- Configured the instance for high concurrency, long-running Node.js processes, and scalable network throughput.
- Built a complete automated deployment pipeline using GitHub Actions that triggers on pushes to the main branch, pulls the latest code to the server, verifies dependencies, and restarts the application via PM2.
- Designed a three-phase scalability roadmap: load balancer implementation, instance upgrades, and auto-scaling capabilities.
- Delivered a production-ready, secure, scalable infrastructure with minimal manual intervention and reduced long-term DevOps costs.
Technologies: JavaScript, TypeScript, SQA, Node.js, CSS, React, Git, MySQL, Amazon Web Services (AWS), Full-stack, Replit, AWS IoT, CI/CD Pipelines, GitHub Actions, AI Engineering, Claude Code
Secure Crossโplatform Auth Integration for WordPress and Electron
2025 - 2025
Mathpr
- Developed and customized a WordPress plugin to extend platform functionality. Created and integrated REST APIs to authenticate user logins with external software systems.
- Developed a cross-platform local software application using ElectronJS, compatible with both Windows and macOS.
- Implemented secure API integrations between the software and WordPress for user authentication.
- Automated user logins to third-party websites without exposing actual credentials to employees.
- Utilized relevant Node.js packages to enhance functionality and streamline development.
Technologies: Front-end, User Experience (UX), Web Development, Back-end, Web Scraping, WordPress, WordPress Plugins, Electron, Automation, Web Security, Web API, HTML5, Recommendation Systems, Technical Requirements, Full-stack Development, No-code Development, Integration, API Development, AI Agents, Data Annotation
Full-stack Developer
2025 - 2025
Codewarranty
- Designed and developed the full-stack CodeWarranty application using MongoDB, Express.js, React, and Node.js, showcasing end-to-end technical proficiency.
- Created responsive, intuitive user interfaces with React, enhancing user engagement across devices.
- Built robust RESTful APIs enabling efficient and secure client-server communication.
- Integrated automated testing suites (unit and integration tests) to ensure high code quality and application stability.
- Implemented user feedback loops and analytics tools to continuously refine features and optimize user experience.
Technologies: MongoDB, Express.js, React, Node.js, SendGrid, APIs, IT Management, Platform as a Service (PaaS), Startups, Software Development, System Architecture, Web Development, Web App Development, API Integration, Next.js, Website Design, Amazon Web Services (AWS), Full-stack, Front-end, Authentication, Automation, Technical Leadership, Software Architecture, Websites, Microsoft Excel, JSON, REST, Front-end Development, OpenAI, AI Chatbots, Minimum Viable Product (MVP), Databases, Tailwind CSS, Figma, Google Tag Manager, Web Design, Back-end Development, Database Architecture, Web Applications, ChatGPT, OpenAI GPT-4 API, API Architecture, Project Management, Communication, System Integration, HTTPS, Web API, Cloud, API Databases, Software as a Service (SaaS), HTML5, HTML Templates, Artificial Intelligence (AI), Recommendation Systems, Technical Requirements, Full-stack Development, OpenAI API, SaaS, No-code Development, Integration, Social Media Content, API Development, PDF, AI Agents, Vercel, White Labeling, AI Engineering, Twilio, Data Annotation, Fastify, DNS, GoDaddy, Email, Claude Code, Fractional CTO
Full-stack Developer
2019 - 2025
CodeNomad Private Limited
- Extensive experience in back-end development using Python, building RESTful APIs, and integrating third-party services to extend application capabilities.
- Spearheaded digital transformation at Jacana Warranty, replacing legacy workflows with automated claim systems.
- Built and scaled custom ERP modules used by electronics brands across India and the US.
- Skilled in PHP web development, leveraging frameworks like Laravel and CodeIgniter to create dynamic, maintainable, and secure applications.
- Deep expertise in WordPress development, including custom theme and plugin creation, ensuring adherence to best practices and delivering exceptional user experiences.
- Strong knowledge of database design, management, and optimization, proficient with both SQL and NoSQL databases, capable of designing efficient data models.
- Experienced in collaborating with cross-functional and agile teams, with a strong focus on timely project delivery and maintaining high-quality code standards.
Technologies: PHP, WordPress, MongoDB, Express.js, React, IT Project Management, Amazon EC2, Amazon S3 (AWS S3), Firebase, Responsive UI, Web, Google Sheets, Google Apps Script, Back-end, Google Sheets API, MySQL, Web Development, Web App Development, System Architecture, Software Development, Zapier, Laravel 11, Content Management Systems (CMS), eCommerce, Payment Gateways, Angular, NestJS, Full-stack, SQL, Web UI Design, UI Design, User Experience (UX), Responsive Web Design (RWD), WooCommerce, Python, OpenAI API, UX Design, User Interface (UI), Front-end, Authentication, Automation, Mobile App Development, React Native, Websites, Microsoft Excel, JSON, REST, Native Mobile Apps, Android, iOS, Front-end Development, OpenAI, Website Data Scraping, AI Chatbots, Minimum Viable Product (MVP), Databases, Tailwind CSS, Figma, Google Tag Manager, Web Design, Back-end Development, PostgreSQL, Database Architecture, Web Applications, WordPress Themes, GraphQL, Shopify, Mobile App Design, ChatGPT, OpenAI GPT-4 API, API Architecture, Project Management, Communication, System Integration, Web Scraping, Data Scraping, HTTPS, Web API, Bots, Cloud, API Databases, Software as a Service (SaaS), HTML5, HTML Templates, Artificial Intelligence (AI), Recommendation Systems, Technical Requirements, Full-stack Development, SaaS, Next.js, Integration, Social Media Content, API Development, PDF, AI Agents, GitHub Actions, Vercel, White Labeling, AI Engineering, Twilio, Data Annotation, Fastify, DNS, GoDaddy, Email, Fractional CTO
Freelance Developer
2013 - 2019
Freelancer
- Developed a custom CRM system using Laravel with advanced filters, multi-role access, and export-ready reports to streamline client lead management and daily operations.
- Integrated Stripe and PayPal payment gateways into React apps with a secure Node.js back end, handling recurring billing and transaction history for users.
- Implemented secure JWT-based authentication across multiple MERN applications, enabling smooth user access and session management for SaaS clients.
Technologies: PHP, Laravel, WordPress, MongoDB, Node.js, React, JavaScript, HTML, CSS, TypeScript, Express.js, GraphQL, REST APIs, Vue, Back-end, MySQL, Full-stack, MySQLi, SQL, WooCommerce, Stripe, Stripe API, OAuth, Webhooks, Microsoft Excel, JSON, REST, Android, iOS, Front-end Development, Website Data Scraping, Databases, Figma, Google Tag Manager, Web Design, Back-end Development, Web Applications, WordPress Themes, Shopify, Mobile App Design, API Architecture, Project Management, Communication, Data Scraping, HTTPS, Web API, Bots, Cloud, HTML5, Technical Requirements, Full-stack Development, API Development, GoDaddy
Junior Back-end Developer
2012 - 2013
Stellen Infotech
- Developed a custom cake builder tool from scratch. It used JavaScript on the front end and PHP with Imagick on the back end to overlay images and generate a fully customized cake design.
- Created multiple WordPress plugins for custom business needs. Designed and deployed plugins to add custom post types, automate tasks, and extend WooCommerce functionality.
- Optimized back-end queries to improve page load speed by 30%. Refactored inefficient database calls in a CodeIgniter 3 project, resulting in noticeably faster performance.
Technologies: PHP, CakePHP, CodeIgniter 3, jQuery, WordPress, HTML, CSS, Joomla, JavaScript, Back-end, WooCommerce, Microsoft Excel, JSON, REST, iOS, Front-end Development, Databases, Web Design, Back-end Development, Web Applications, WordPress Themes, API Architecture, Communication, HTTPS, Cloud
Experience
AI Assistant ChatBot with 90% Token Cost Optimization
Built an intelligent AI-powered chatbot trained on 13 years of professional experience, enabling natural conversations about skills, projects, and career history. The core engineering challenge was the cost of the OpenAI API token: every message required sending the full 13-year context, making it economically unsustainable.
Solved this by implementing ephemeral cache control that stores conversation context for 5 minutes per session. This single optimization reduced token consumption by 90%, making the chatbot viable for production.
Key technical achievements:
โข Designed vector-based data storage in Firestore, consolidating multiple API endpoints into a single-point retrieval system, reducing server load significantly.
โข Built an auto-update mechanism that refreshes vector embeddings hourly and a real-time training interface for immediate model updates.
โข Architected the full-stack solution with ExpressJS, Node.js, OpenAI API, Firestore, React, and Next.js.
โข Live at nikhilgarg510.com/chat
Solved this by implementing ephemeral cache control that stores conversation context for 5 minutes per session. This single optimization reduced token consumption by 90%, making the chatbot viable for production.
Key technical achievements:
โข Designed vector-based data storage in Firestore, consolidating multiple API endpoints into a single-point retrieval system, reducing server load significantly.
โข Built an auto-update mechanism that refreshes vector embeddings hourly and a real-time training interface for immediate model updates.
โข Architected the full-stack solution with ExpressJS, Node.js, OpenAI API, Firestore, React, and Next.js.
โข Live at nikhilgarg510.com/chat
Remit Assure: Website and Mobile Application for Money Transfers
โข Led the end-to-end development of the RemitAssure fintech website and mobile app, focused on secure, fast, and reliable international P2P money transfers.
โข Architected and built back-end APIs using Python with Django Rest Framework, ensuring scalable, secure, and efficient data handling.
โข Developed a responsive front end with React, HTML5, CSS, and JavaScript to deliver a seamless user experience across devices.
โข Integrated multiple third-party financial institutions and payment processors via robust API connections, enabling real-time fund reconciliation through webhook-based automation.
โข Designed and implemented advanced KYC (Know Your Customer) workflows and fraud detection logic leveraging coordinated back-end integrations.
โข Prioritized security by incorporating multi-factor authentication, risk-based user verification, and secure data transmission protocols to protect sensitive financial data.
โข Optimized app performance for handling high transaction volumes with scalable cloud infrastructure and caching strategies.
โข Resulted in increased website traffic, improved user trust, and positioning RemitAssure as a competitive leader in international remittances.
โข Architected and built back-end APIs using Python with Django Rest Framework, ensuring scalable, secure, and efficient data handling.
โข Developed a responsive front end with React, HTML5, CSS, and JavaScript to deliver a seamless user experience across devices.
โข Integrated multiple third-party financial institutions and payment processors via robust API connections, enabling real-time fund reconciliation through webhook-based automation.
โข Designed and implemented advanced KYC (Know Your Customer) workflows and fraud detection logic leveraging coordinated back-end integrations.
โข Prioritized security by incorporating multi-factor authentication, risk-based user verification, and secure data transmission protocols to protect sensitive financial data.
โข Optimized app performance for handling high transaction volumes with scalable cloud infrastructure and caching strategies.
โข Resulted in increased website traffic, improved user trust, and positioning RemitAssure as a competitive leader in international remittances.
Yokohama ATG Warranty Wizard Mobile App
I developed a mobile app integrated with Zendesk REST APIs to enhance customer support interactions for Yokohama ATG.
FEATURES
โข Enables customers to file and submit warranty claims through a seamless mobile interface built with React Native.
โข Implements real-time syncing of Zendesk tickets using webhook listeners and API polling for up-to-date claim status and resolution tracking.
โข Facilitates two-way communication between customers and support agents via Zendesk messaging APIs, improving response time and issue resolution.
โข Manages the entire warranty claim lifecycle, including claim creation, status updates, attachments upload, and resolution documentation.
โข Uses secure OAuth 2.0 authentication to protect customer data and ensure authorized API access.
โข Implements efficient data caching and offline support for improved app responsiveness and usability in low-connectivity areas.
โข Backend services built with Python/Django to handle API requests, ticket synchronization, and claims processing logic.
โข Automates workflows through API triggers to notify users and update tickets automatically upon claim progress.
FEATURES
โข Enables customers to file and submit warranty claims through a seamless mobile interface built with React Native.
โข Implements real-time syncing of Zendesk tickets using webhook listeners and API polling for up-to-date claim status and resolution tracking.
โข Facilitates two-way communication between customers and support agents via Zendesk messaging APIs, improving response time and issue resolution.
โข Manages the entire warranty claim lifecycle, including claim creation, status updates, attachments upload, and resolution documentation.
โข Uses secure OAuth 2.0 authentication to protect customer data and ensure authorized API access.
โข Implements efficient data caching and offline support for improved app responsiveness and usability in low-connectivity areas.
โข Backend services built with Python/Django to handle API requests, ticket synchronization, and claims processing logic.
โข Automates workflows through API triggers to notify users and update tickets automatically upon claim progress.
GetCover
Demonstrated end-to-end full-stack development expertise with MongoDB, Express.js, React, and Node.js, delivering a robust and maintainable application.
Designed and implemented intuitive, responsive user interfaces in React, ensuring seamless cross-device accessibility and a superior user experience.
Developed and maintained efficient RESTful APIs to enable secure, real-time client-server communication and data exchange.
Architected and managed the MongoDB database schema, prioritizing data integrity, security, and scalability for long-term operational stability.
Applied Agile project management methodologies, leveraging iterative development and regular stakeholder feedback to optimize productivity and feature delivery.
Designed and implemented intuitive, responsive user interfaces in React, ensuring seamless cross-device accessibility and a superior user experience.
Developed and maintained efficient RESTful APIs to enable secure, real-time client-server communication and data exchange.
Architected and managed the MongoDB database schema, prioritizing data integrity, security, and scalability for long-term operational stability.
Applied Agile project management methodologies, leveraging iterative development and regular stakeholder feedback to optimize productivity and feature delivery.
Jacana Warranty
WordPress Development: Spearheaded the customization and optimization of Jacana Warrantyโs WordPress site, integrating complex plugins, including Gravity Forms, to streamline warranty registration, resulting in a 30% increase in user submissions and improved data accuracy.
Gravity Forms Integration: Developed advanced multi-step Gravity Forms with conditional logic for warranty claim processing, reducing form abandonment rates by 25% and enhancing back-end data flow for customer service teams.
React Native Mobile Application: Led the design and implementation of Jacana Warrantyโs React Native mobile app, enabling cross-platform warranty management and real-time notifications, boosting active user retention by 40%.
Cross-Functional Collaboration: Partnered with UX designers, QA engineers, and product managers to refine feature requirements and conduct usability testing, ensuring seamless integration of warranty workflows and superior user experience.
Innovative Problem Solving: Engineered custom API integrations between Jacana Warrantyโs WordPress back-end and third-party logistics providers, overcoming data syncing challenges and reducing claim processing time by 35%.
Gravity Forms Integration: Developed advanced multi-step Gravity Forms with conditional logic for warranty claim processing, reducing form abandonment rates by 25% and enhancing back-end data flow for customer service teams.
React Native Mobile Application: Led the design and implementation of Jacana Warrantyโs React Native mobile app, enabling cross-platform warranty management and real-time notifications, boosting active user retention by 40%.
Cross-Functional Collaboration: Partnered with UX designers, QA engineers, and product managers to refine feature requirements and conduct usability testing, ensuring seamless integration of warranty workflows and superior user experience.
Innovative Problem Solving: Engineered custom API integrations between Jacana Warrantyโs WordPress back-end and third-party logistics providers, overcoming data syncing challenges and reducing claim processing time by 35%.
Doctome
https://doctome.co.il/Project Contributions: Led the migration of Doctome's legacy system to Laravel, improving back-end stability and security while overcoming integration challenges with existing APIs.
Achievements: Optimized front-end load times by 40% through code refactoring and asset management, significantly improving user engagement on Doctomeโs patient portal.
Collaboration: Coordinated with UI/UX designers, medical professionals, and marketing teams to deliver a seamless multi-stakeholder platform aligned with healthcare compliance standards.
Problem Solving: Implemented a dynamic notification system within Laravel to handle real-time updates for doctors and patients, resolving issues of delayed communications.
User Experience Focus: Spearheaded redesign initiatives focusing on responsive front-end interfaces, resulting in a 25% increase in mobile user retention for Doctome services.
Achievements: Optimized front-end load times by 40% through code refactoring and asset management, significantly improving user engagement on Doctomeโs patient portal.
Collaboration: Coordinated with UI/UX designers, medical professionals, and marketing teams to deliver a seamless multi-stakeholder platform aligned with healthcare compliance standards.
Problem Solving: Implemented a dynamic notification system within Laravel to handle real-time updates for doctors and patients, resolving issues of delayed communications.
User Experience Focus: Spearheaded redesign initiatives focusing on responsive front-end interfaces, resulting in a 25% increase in mobile user retention for Doctome services.
iDispatch MobilityโA Global Cab Service Provider
โข Led the full-stack development using MERN stack (MongoDB, Express.js, React, and Node.js) to build a scalable, cloud-hosted cab management platform.
โข Designed and implemented RESTful APIs and back-end services, ensuring efficient data flow and real-time trip management with WebSocket integration.
โข Managed cloud infrastructure on AWS for reliable hosting, auto-scaling, and optimized performance with a focus on high availability.
โข Implemented secure authentication mechanisms using OAuth 2.0 and ensured compliance with GDPR and other data privacy regulations.
โข Configured CI/CD pipelines and automated deployments to accelerate release cycles and maintain code quality.
โข Oversaw Docker containerization and orchestration for consistent, portable development, testing, and production environments.
โข Integrated Google Maps API for accurate GPS tracking and enhanced map visualization in both web and mobile apps.
โข Collaborated on implementing background location tracking beyond platform restrictions on iOS and Android.
โข Ensured data encryption and security protocols, including SSL and two-factor authentication, for secure payment transactions.
โข Designed and implemented RESTful APIs and back-end services, ensuring efficient data flow and real-time trip management with WebSocket integration.
โข Managed cloud infrastructure on AWS for reliable hosting, auto-scaling, and optimized performance with a focus on high availability.
โข Implemented secure authentication mechanisms using OAuth 2.0 and ensured compliance with GDPR and other data privacy regulations.
โข Configured CI/CD pipelines and automated deployments to accelerate release cycles and maintain code quality.
โข Oversaw Docker containerization and orchestration for consistent, portable development, testing, and production environments.
โข Integrated Google Maps API for accurate GPS tracking and enhanced map visualization in both web and mobile apps.
โข Collaborated on implementing background location tracking beyond platform restrictions on iOS and Android.
โข Ensured data encryption and security protocols, including SSL and two-factor authentication, for secure payment transactions.
CodeWarranty - Enterprise Warranty Management SaaS
https://codewarranty.comBuilt CodeWarranty from the ground up as Founder and Technical Architect. CodeWarranty is a SaaS warranty management platform serving solar systems, appliances, consumer electronics, and EV chargers across multi-stakeholder ecosystems involving OEMs, distributors, service centers, and end customers.
Key contributions:
โข Designed multi-tenant RBAC architecture for complex stakeholder hierarchies
โข Implemented AI-powered fraud detection with pattern recognition
โข Achieved 75% faster claim processing via automated workflows
โข Reduced operational complexity by 60% over manual processes
โข Built configurable compliance modules for multi-industry regulatory requirements
โข Integrated Stripe payments, AWS infrastructure, and Docker containers
โข Delivered a real-time analytics dashboard with fraud detection reporting
Full-stack solution built with React, Node.js, MongoDB, Express, JWT, Stripe, AWS, and Docker.
Key contributions:
โข Designed multi-tenant RBAC architecture for complex stakeholder hierarchies
โข Implemented AI-powered fraud detection with pattern recognition
โข Achieved 75% faster claim processing via automated workflows
โข Reduced operational complexity by 60% over manual processes
โข Built configurable compliance modules for multi-industry regulatory requirements
โข Integrated Stripe payments, AWS infrastructure, and Docker containers
โข Delivered a real-time analytics dashboard with fraud detection reporting
Full-stack solution built with React, Node.js, MongoDB, Express, JWT, Stripe, AWS, and Docker.
Firestarter AI Shopping Assistant - Shopify App
https://apps.shopify.com/firestarter-ai-shoppingBuilt and launched Firestarter AI as a full-stack Shopify app that transforms eCommerce product discovery through natural language conversations. Customers describe what they want in plain English across 30+ languages, in text or voice, and the AI intelligently matches them with products from the store's inventory.
The app was approved and published on the official Shopify App Store, meeting Shopify's strict security, performance, and UX requirements.
Key technical contributions:
โข Built a complete React admin dashboard using Shopify Polaris and App Bridge
โข Developed a theme extension chat widget that integrates seamlessly with any Shopify theme via the native app embed system
โข Implemented real-time product synchronization from Shopify to Supabase via webhook-based delta updates
โข Integrated voice functionality using OpenAI GPT Voice API for conversational shopping
โข Built semantic search leveraging product descriptions, attributes, and customer intent analysis
โข Architected OAuth 2.0 flows, Shopify REST and GraphQL APIs, PostgreSQL, and Node.js back end.
The app was approved and published on the official Shopify App Store, meeting Shopify's strict security, performance, and UX requirements.
Key technical contributions:
โข Built a complete React admin dashboard using Shopify Polaris and App Bridge
โข Developed a theme extension chat widget that integrates seamlessly with any Shopify theme via the native app embed system
โข Implemented real-time product synchronization from Shopify to Supabase via webhook-based delta updates
โข Integrated voice functionality using OpenAI GPT Voice API for conversational shopping
โข Built semantic search leveraging product descriptions, attributes, and customer intent analysis
โข Architected OAuth 2.0 flows, Shopify REST and GraphQL APIs, PostgreSQL, and Node.js back end.
Satsman - Production AWS Migration and CI/CD for AI-generated Codebase
https://satsman.comHired via Toptal to transform a Replit AI-generated prototype into a production-grade AWS deployment. The client was building the Satsman platform using Replit's Vibe Coding tool, but and into limitations when the AI got stuck and lacked production infrastructure.
Delivered end-to-end infrastructure setup and DevOps implementation:
โข Migrated entire application from Replit to self-hosted AWS (EC2 instances, load balancers, auto-scaling groups)
โข Built a complete CI/CD pipeline using GitHub Actions, enabling push-to-deploy directly from Replit through GitHub to production
โข Implemented enterprise-grade security hardening and production best practices for AI-generated code
โข Provided hands-on development support both inside Replit for rapid iteration and in the codebase for production bug fixes
โข Resolved complex issues where AI code generation tools got stuck or produced incorrect output
Tech stack: React, Node.js, PostgreSQL (Neon), Stripe, Stripe Connect, Anthropic API, AWS EC2, AWS Load Balancers, GitHub Actions, CI/CD
Delivered end-to-end infrastructure setup and DevOps implementation:
โข Migrated entire application from Replit to self-hosted AWS (EC2 instances, load balancers, auto-scaling groups)
โข Built a complete CI/CD pipeline using GitHub Actions, enabling push-to-deploy directly from Replit through GitHub to production
โข Implemented enterprise-grade security hardening and production best practices for AI-generated code
โข Provided hands-on development support both inside Replit for rapid iteration and in the codebase for production bug fixes
โข Resolved complex issues where AI code generation tools got stuck or produced incorrect output
Tech stack: React, Node.js, PostgreSQL (Neon), Stripe, Stripe Connect, Anthropic API, AWS EC2, AWS Load Balancers, GitHub Actions, CI/CD
DiversiFIT - Legacy MERN Fitness App Modernization and API Migration
https://diversifit.ioHired via Toptal to modernize DiversiFIT, a fitness platform built in 2017 and last updated in 2019. The platform connects gyms, trainers, and members through Mindbody integration and faced a critical shutdown risk when Mindbody deprecated its legacy XML APIs.
Delivered complete legacy modernization across the full stack:
โข Successfully set up and containerized a 7-year-old codebase with broken Docker config and outdated dependencies
โข Migrated the entire Mindbody integration from deprecated XML APIs to modern v6 REST APIs with zero downtime, including OAuth 2.0 authentication and full endpoint remapping
โข Upgraded the React Native mobile app beyond Expo SDK 51 lock-in, resolving breaking changes for both iOS and Android
โข Modernized Google Cloud deployment with Kubernetes orchestration and updated CI/CD pipeline
โข Created comprehensive setup documentation to prevent future maintenance challenges
Tech stack: React, Node.js, Express, MongoDB, React Native, Expo SDK, Google Cloud Platform, Kubernetes, Docker, Mindbody API v6, OAuth 2.0, GitHub Actions
Delivered complete legacy modernization across the full stack:
โข Successfully set up and containerized a 7-year-old codebase with broken Docker config and outdated dependencies
โข Migrated the entire Mindbody integration from deprecated XML APIs to modern v6 REST APIs with zero downtime, including OAuth 2.0 authentication and full endpoint remapping
โข Upgraded the React Native mobile app beyond Expo SDK 51 lock-in, resolving breaking changes for both iOS and Android
โข Modernized Google Cloud deployment with Kubernetes orchestration and updated CI/CD pipeline
โข Created comprehensive setup documentation to prevent future maintenance challenges
Tech stack: React, Node.js, Express, MongoDB, React Native, Expo SDK, Google Cloud Platform, Kubernetes, Docker, Mindbody API v6, OAuth 2.0, GitHub Actions
MHHC Enterprises - B2B Warranty Management Platform on WordPress
https://portal.warrantyandservices.com/mhhc-login/Built a comprehensive RBAC warranty management system for MHHC Enterprises, a US OTC market-registered company drowning in warranty debt with 10+ years of unstructured Excel data. MHHC reached out after seeing my work with Jacana Warranty, needing urgent tech support to handle their warranty management crisis.
Delivered a complete WordPress-based enterprise solution that cleared their massive backlog and improved their relationship with their biggest client, CPS Central:
โข Migrated 10+ years of unstructured Excel warranty data into a clean, organized digital platform using custom PHP data cleansing scripts
โข Built enterprise-level RBAC system with custom WordPress user roles, capabilities, and meta fields
โข Integrated PayPal payment processing for warranty claims and automated transaction tracking
โข Built custom API endpoints and a client portal with real-time claim status updates for CPS Central integration
โข Reduced claim processing from days to hours and eliminated 80% of manual processes
Client testimonial: "Nikhil transformed our decade-old Excel system into a modern warranty platform." - Vincent Lewis, President of Operations, MHHC Enterprises Inc
Delivered a complete WordPress-based enterprise solution that cleared their massive backlog and improved their relationship with their biggest client, CPS Central:
โข Migrated 10+ years of unstructured Excel warranty data into a clean, organized digital platform using custom PHP data cleansing scripts
โข Built enterprise-level RBAC system with custom WordPress user roles, capabilities, and meta fields
โข Integrated PayPal payment processing for warranty claims and automated transaction tracking
โข Built custom API endpoints and a client portal with real-time claim status updates for CPS Central integration
โข Reduced claim processing from days to hours and eliminated 80% of manual processes
Client testimonial: "Nikhil transformed our decade-old Excel system into a modern warranty platform." - Vincent Lewis, President of Operations, MHHC Enterprises Inc
Education
2008 - 2012
Bachelor's Degree in Engineering
Panjab University - Chandigarh, India
Skills
Libraries/APIs
API Development, Node.js, REST APIs, OpenAI API, Twilio API, Web API, React, jQuery, Vue, Google Sheets API, Authorize.net, UPS API, WhatsApp API, Stripe, Stripe API, Zendesk API, Google Maps API, Winston, Sidekiq
Tools
GravityView, Gravity Perks, Claude Code, Jira, GitHub, Figma, ChatGPT, SendGrid, Google Sheets, Zapier, Git, Auth0, Microsoft Excel, HashiCorp Vault, Grafana, Amazon ElastiCache, Kafka Connect, RabbitMQ, Celery, Vault
Languages
PHP, HTML5, HTML, CSS, JavaScript, TypeScript, GraphQL, Google Apps Script, SQL, Python, Python 3
Frameworks
Next.js, Express.js, Tailwind CSS, Fastify, Laravel, CakePHP, CodeIgniter 3, Laravel 11, Angular, NestJS, React Native, CodeIgniter, Django, Electron, Spring Boot, OAuth 2, JSON Web Tokens (JWT), Jest
Paradigms
REST, B2B2C, Automation, Mobile App Design, API Architecture, Web UI Design, UI Design, Responsive Web Design (RWD), Agile, UX Design, ACID, Role-based Access Control (RBAC), DevOps
Platforms
WordPress, Web, Android, iOS, Shopify, Vercel, Twilio, Amazon EC2, Joomla, Firebase, Amazon Web Services (AWS), WooCommerce, Zendesk, Replit, AWS IoT, Docker, Kubernetes
Storage
JSON, Databases, MongoDB, Amazon S3 (AWS S3), Database Architecture, API Databases, MySQL, MySQLi, PostgreSQL, Redis
Industry Expertise
Web Design, Project Management
Other
APIs, IT Project Management, Gravity Forms, IT Management, SaaS, Minimum Viable Product (MVP), Back-end Development, Web Applications, Communication, HTML Templates, Recommendation Systems, Technical Requirements, Full-stack Development, Integration, Fractional CTO, Software, Front-end Development, OpenAI, Website Data Scraping, Google Tag Manager, Cross-platform App Development, WordPress Themes, OpenAI GPT-4 API, AI Tools, System Integration, Data Scraping, HTTPS, Cloud, Software as a Service (SaaS), Artificial Intelligence (AI), No-code Development, Social Media Content, PDF, AI Agents, GitHub Actions, White Labeling, AI Engineering, Supabase, Data Annotation, DNS, GoDaddy, Email, Responsive UI, Platform as a Service (PaaS), Startups, Back-end, Software Development, System Architecture, Web Development, Web App Development, API Integration, Website Design, Content Management Systems (CMS), eCommerce, Payment Gateways, Full-stack, User Experience (UX), Elementor, User Interface (UI), Front-end, Authentication, OAuth, Webhooks, Technical Leadership, Software Architecture, Mobile App Development, Websites, Native Mobile Apps, AI Chatbots, Fraud Prevention, WebSockets, PayPal, Web Scraping, WordPress Plugins, Web Security, Payment Processing, Bots, Fintech, SQA, CI/CD Pipelines, Payments, FastAPI, Row-level Security (RLS), Efficient Data Serialization, Open Banking APIs, AWS Secrets Manager, Prometheus, Amazon RDS, Ledgers, BullMQ, GCP DevOps, Architecture
Collaboration That Works
How to Work with Toptal
Toptal matches you directly with global industry experts from our network in hoursโnot weeks or months.
1
Share your needs
Discuss your requirements and refine your scope in a call with a Toptal domainย expert.
2
Choose your talent
Get a short list of expertly matched talent within 24 hours to review, interview, and chooseย from.
3
Start your risk-free talent trial
Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hireย them.
Top talent is in high demand.
Start hiring