Sandeep Amarnath, Developer in Toronto, ON, Canada
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Sandeep Amarnath

Bio

Sandeep is a senior React Native engineer with 7+ years of experience building high-performance mobile and web applications. He's led front-end migrations, improving load times by 30%, and built production apps from scratch. At companies like OANDA, Sandeep has delivered scalable solutions serving thousands of users with React Native, React, and TypeScript.

Portfolio

Staples Canada ULC
React, Shopify, Algolia, Contentful, Shopify Storefront API...
Quartermaster
React, React Native, TypeScript, NoSQL, Zustand, Auth0, APIs, API Integration...
Oanda
React, Redux, TypeScript, Node.js, Express.js, State Machines, MongoDB...

Experience

  • React Native - 7 years
  • TypeScript - 7 years
  • JavaScript - 7 years
  • React - 7 years
  • Redux - 6 years
  • Node.js - 5 years
  • Expo - 4 years
  • Zustand - 2 years

Preferred Environment

React Native, React

The most amazing...

...solution I've built is a React Native marketplace app from scratch that now serves thousands of daily users with real-time chat and AI features.

Work Experience

Tech Lead

2026 - PRESENT
Staples Canada ULC
  • Led front-end development for staples.ca within a React/Shopify architecture, managing integrations across Algolia search, Akeneo PIM, and Shopify Storefront API, serving millions of Canadian customers.
  • Managed a cross-functional team of 4 developers conducting code reviews, sprint planning, and tech feasibility assessments while negotiating sprint priorities with Product Management to balance feature delivery and technical debt reduction.
  • Orchestrated Bootstrap 4 to 5 migration to meet compliance requirements, establishing a comprehensive UI test suite from scratch to validate component behavior across breaking changes, ensuring zero customer-facing regressions during deployment.
  • Drove technical research and vendor coordination for RichRelevance-to-data science API migration, working with external consultants and internal teams to architect a phased transition strategy while maintaining email personalization functionality.
  • Resolved critical production incidents impacting revenue through systematic debugging across multi-system data flows, including a duplicate SKU issue that uncovered $40,000 in lost revenue over a 3-day period within the first two weeks of the role.
Technologies: React, Shopify, Algolia, Contentful, Shopify Storefront API, Full-stack Development, Full-stack, AI Tools

Senior Software Developer

2024 - 2025
Quartermaster
  • Led front-end migration from a React and Angular hybrid to modern React architecture, reducing page load times by 30% and improving maintainability.
  • Built React Native mobile applications for homeowners and professionals from scratch, independently managing the entire mobile development lifecycle.
  • Developed real-time chat features using Stream Chat, transitioning from a project-based to a single-channel model that improved user engagement.
  • Created a reusable UI component library using React and Storybook, following WCAG accessibility standards to ensure design consistency.
Technologies: React, React Native, TypeScript, NoSQL, Zustand, Auth0, APIs, API Integration, Next.js, MUI CSS, Front-end, Claude Code, Cursor AI, Styled-components, Marketplaces, Full-stack, Tailwind CSS, AI Tools, NestJS, Integration

Software Engineer

2021 - 2023
Oanda
  • Built a multi-step onboarding application handling 15+ country-specific regulatory requirements, reducing client drop-off rates by streamlining the form experience across different jurisdictions.
  • Implemented complex state management using Redux to handle dynamic form validations, ensuring data persistence across 8-12 form steps while maintaining compliance with financial regulations.
  • Collaborated with compliance and product teams to integrate real-time API validation, reducing onboarding errors by catching regulatory issues before form submission.
  • Optimized application performance by implementing lazy loading and code splitting, reducing initial load time by 40% for users accessing the onboarding flow.
Technologies: React, Redux, TypeScript, Node.js, Express.js, State Machines, MongoDB, JavaScript, Auth0, APIs, API Integration, MUI CSS, Front-end, Full-stack Development, Full-stack, Amazon Web Services (AWS), OAuth 2

Consultant

2018 - 2021
FDM group
  • Completed an intensive software development training program covering React, TypeScript, SQL, and professional best practices in preparation for client placement.
  • Built an internal project management tool during training using React and Node.js, enabling trainers to track cohort progress and assignment submissions more efficiently.
  • Created a training resource library application using React, centralizing learning materials and coding exercises for future cohorts to access and utilize.
Technologies: JavaScript, TypeScript, React, Google Sheets API, APIs, API Integration, Front-end

Software Developer

2018 - 2021
Mackenzie Investments
  • Developed interactive portfolio analytics dashboards using React and TypeScript, enabling financial advisors to visualize client investment performance across multiple fund categories.
  • Implemented data visualization components for fund performance tracking, improving user engagement with complex financial data through intuitive charts and graphs.
  • Collaborated with the compliance team to ensure all client-facing features met regulatory requirements for Canadian financial services, maintaining 100% audit compliance.
  • Optimized SQL queries for portfolio data retrieval, reducing page load times by 35% for advisors accessing client account information across thousands of records.
  • Built reusable UI components for displaying fund information, creating a consistent design system used across multiple internal and client-facing applications.
Technologies: React, SQL, TypeScript, JavaScript, CSS, HTML, SendGrid API, Google Sheets API, APIs, API Integration, Front-end

Experience

Cash Transaction Tracker

A React Native mobile app that solves the key limitations of existing expense-splitting tools like Splitwise. We built a custom cash transaction management solution with features including real-time balance tracking, multi-currency support, and offline-first architecture. We also developed a companion landing page with a demo video to showcase functionalities and attract clients. The technologies we leveraged included React Native, Expo, MongoDB, and Node.js.

Home Service Marketplace App at Quartermaster

A React Native app built end-to-end for a home service marketplace, and also the service professionals' side of the app. These two apps help homeowners find the right service professionals for home-related projects, like painting, plumbing, and more.

Onboarding Application at OANDA

https://auth.oanda.com/u/login?
A React app I built for onboarding clients at OANDA (Forex trading platform). This app involves a multipart form and a complex state management system, as each country's onboarding pages differ. I implemented client-side validation, multi-step form navigation, and dynamic form rendering based on regulatory requirements. The application handled sensitive financial data in compliance with strict standards, integrating with OANDA's back-end APIs for real-time validation and data persistence. I worked closely with product and compliance teams to ensure the onboarding flow met all regulatory requirements across different jurisdictions.

Education

2017 - 2018

Master's Degree in Computer Networking

Dalhousie University - Halifax, Canada

Skills

Libraries/APIs

React, Node.js, NativeWind, SendGrid API, Google Sheets API, Shopify Storefront API

Tools

Claude Code, Expo, Auth0

Languages

TypeScript, JavaScript, HTML, CSS, SQL

Frameworks

React Native, Tailwind CSS, Next.js, MUI CSS, NestJS, OAuth 2, Redux, Material UI, Express.js

Storage

NoSQL, MongoDB

Platforms

Amazon Web Services (AWS), Shopify, Algolia, Contentful

Other

Web Development, APIs, Front-end, Full-stack Development, AI Tools, Zustand, API Integration, Full-stack, Cursor AI, Styled-components, Marketplaces, Supabase, Integration, State Machines

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