Harsh Gupta, Developer in Galway, Ireland
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Harsh Gupta

Verified Expert  in Engineering

Software Developer

Galway, Ireland
Toptal Member Since
November 1, 2021

Harsh is an experienced software engineer with profound expertise in JavaScript, TypeScript, Next.js, and React. Over eight years, he's developed exceptional web applications, focusing on system design, thorough documentation, and meticulous testing to ensure the highest product quality. Harsh's background in blockchain and his role in creating impactful, tech-driven solutions showcase his ability to deliver robust, high-performing software tailored to meet diverse client needs.


Passport V3
Express.js, React Redux, Firebase, React, Solidity, Stripe API...
W3Blendr Ltd.
Docker, TypeScript, Next.js, NestJS, Python 3, BigQuery, PostgreSQL, GraphQL...
Java 8, Spring 4, JUnit, Docker, Jenkins, CI/CD Pipelines, GitHub, APIs...




Preferred Environment

Visual Studio Code (VS Code), TypeScript, Next.js, Jest, React, NestJS, Git, Amazon Web Services (AWS)

The most amazing...

...thing: a Web3 behavioral finance platform with a NestJS back end and a Next.js front end, using subgraphs and Solidity contracts for trader behavior analysis.

Work Experience


2023 - 2024
Passport V3
  • Architected a comprehensive system and microservice architecture using AWS components, enhancing scalability and reliability for a Web3 lifestyle and loyalty app.
  • Developed a proof of concept for a mobile application using Flutter, which accelerated the company's efforts in securing approximately $600,000 in an angel investment round.
  • Strategized the cryptocurrency utility and tokenomics based on successful project whitepapers, resulting in the creation and integration of a token using OpenZeppelin, Hardhat, and Uniswap SDK.
  • Implemented automated minting and burning functionalities, enabling the distribution of SAFT agreements valued at $225,000 within a month of launch.
  • Built an in-house CMS system using Next.js and TypeScript to manage bookings, events, and cryptocurrency-supported in-app payments, streamlining operations across multiple user interfaces.
  • Integrated Stripe checkout for fiat transactions, handling approximately $10,000 in daily revenue generation through streamlined payment processes.
  • Orchestrated the development of virtual pre-paid crypto cards for use in Dubai, expanding payment options and enhancing user engagement.
  • Led the growth of the product to 1000 monthly active users, making multiple bookings, significantly boosting user engagement and market penetration.
  • Managed a team of 15 engineers across multiple disciplines, successfully meeting every milestone in the development roadmap and contributing to the MVP launch.
Technologies: Express.js, React Redux, Firebase, React, Solidity, Stripe API, Visual Studio Code (VS Code), Node.js, NestJS, Smart Contracts, Web3.js, Next.js, TypeScript, System Design, Python, CTO, Machine Learning, API Integration, NoSQL, Testing, SQL, Front-end, Object-oriented Programming (OOP), Web3, Subgraph, GraphQL, MongoDB, Architecture, Tailwind CSS, CI/CD Pipelines, APIs, Amazon Web Services (AWS), OpenZeppelin, Hardhat, Uniswap SDK, GitHub Runners, GitHub Actions


2022 - 2024
W3Blendr Ltd.
  • Developed system architecture using AWS components, creating a robust, scalable platform for analyzing behavioral finance data from blockchain transactions.
  • Designed a data model to store, transform, and analyze blockchain transaction data using tools like Dask, Google BigQuery, AWS RDS, MongoDB, and GraphQL, which supported advanced analytics capabilities.
  • Created a microservice architecture for the system's back end, incorporating OAuth, Python, NestJS, Docker, and AWS EKS to enhance security and modularity.
  • Engineered asynchronous communication between services using AWS SQS, which improved interaction efficiency by 80% compared to previous synchronous communication systems.
  • Crafted the front-end's UI/UX using Figma, React, Tailwind CSS, Next.js, TypeScript, and D3.js. This resulted in a user-friendly interface that facilitated over 50 user adoptions in the first month.
  • Initiated and led the development of machine learning proofs of concept to classify Web3 wallets and recommend tokens to users, enhancing portfolio suitability with accuracies of approximately 66% and 53%, respectively.
  • Implemented continuous integration and deployment using GitHub Actions and Jenkins, ensuring seamless, error-free releases.
  • Established a continuous learning pipeline for updating machine learning models with new data, maintaining high accuracy and relevance of analytical tools.
  • Managed a team of nine engineers, including full-stack engineers, DevOps, SQAs, and a data science team, achieving every milestone in the development roadmap.
  • Strategized sales and client acquisition, achieving initial sales of approximately $120,000, and prepared comprehensive business models and pitch decks for investor and client presentations.
Technologies: Docker, TypeScript, Next.js, NestJS, Python 3, BigQuery, PostgreSQL, GraphQL, Solidity, Web3.js, Ethers.js, Generative Adversarial Networks (GANs), Data Analytics, Agile Sprints, Node.js, Smart Contracts, React Redux, System Design, Python, CTO, Machine Learning, API Integration, NoSQL, Data Science, Django, Testing, SQL, Front-end, Object-oriented Programming (OOP), D3.js, Web3, AWS Lambda, Amazon S3 (AWS S3), Amazon Elastic Container Service (Amazon ECS), Amazon RDS, Architecture, Tailwind CSS, CI/CD Pipelines, APIs, Dask, Figma, GitHub Actions, Jenkins, Machine Learning Operations (MLOps)

Senior Software Engineer

2023 - 2023
  • Led the development of CarTrawler's booking engine using the Spring Framework, significantly enhancing the application's functionality and user experience.
  • Deployed updates and enhancements efficiently using Jenkins and AWS, ensuring high availability and performance of the booking engine.
  • Implemented an end-to-end push notification system using Java, YAML, Python, and MongoDB. This system automated communication with users based on their booking details, improving customer engagement and satisfaction.
Technologies: Java 8, Spring 4, JUnit, Docker, Jenkins, CI/CD Pipelines, GitHub, APIs, Python 3, Firebase, Push Notifications, Amazon Web Services (AWS), Amazon EKS, MongoDB

Senior Software Engineer

2022 - 2023
  • Improved the Kafka streaming service used for data streaming from nodes, reducing latency by 30% and enhancing overall system performance.
  • Created comprehensive test plans and conducted end-to-end testing for feature releases, achieving a 95% decrease in post-release bugs and issues.
  • Spearheaded the creation and implementation of an end-to-end testing tool for the performance management application, which reduced manual testing time by up to 90% and significantly increased testing efficiency.
Technologies: Java 8, Apache Kafka, JUnit, Visual Studio Code (VS Code), Software Engineering, Artificial Intelligence (AI), Data Analytics, Agile Sprints, JavaScript, Scikit-learn, TypeScript, System Design, Generative AI, Python, API Integration, Testing, SQL, Object-oriented Programming (OOP), CI/CD Pipelines, APIs, RHEL, Jenkins, Groovy, Cucumber, Docker

Product Owner

2022 - 2022
  • Analyzed product requirements and collaborated with scrum masters to prioritize features, resulting in a 20% increase in on-time feature releases and significantly improving project timelines and deliverables.
  • Led the planning and execution of development cycles for user stories, tasks, spikes, and test plans, which enhanced feature implementation and led to a 15% improvement in overall product quality.
  • Designed and implemented innovative solutions in collaboration with cross-functional teams, reducing customer-experienced bugs by 10% and enhancing the user experience across multiple platforms.
Technologies: Jira, Office 365, Confluence, Python 3, Bash

Solidity Developer

2021 - 2022
Jose Miguel Vera Jimenez
  • Developed the front end using React and Tailwind CSS.
  • Used a test-driven development approach to make sure the components were well-tested.
  • Oversaw the launch of the website, which resulted in global availability.
Technologies: Solidity, Smart Contracts, React, Ethers.js, Web3.js, Jest, Visual Studio Code (VS Code), Software Engineering, Agile Sprints, JavaScript, Node.js, Next.js, TypeScript, React Redux, Testing, SQL, Web3, Tailwind CSS, APIs

Innovation Driver

2020 - 2022
  • Utilized generative adversarial networks in TensorFlow to develop an anomaly detection and correction system. Due to its innovative approach and high impact on network security, it was recognized with the Best Tech Award at a major tech competition.
  • Designed and executed a Proof of Concept (PoC) for the UN's World Hackathon, which enabled easier access to advanced technology studies and secured 6th place among global participants, showcasing the project's relevance and effectiveness.
  • Engineered a system to extend 5G network services underwater, which led to a third-place win in an Ericsson Innovation competition and demonstrated groundbreaking advancements in extending network capabilities to challenging environments.
Technologies: Agile Sprints, Generative Adversarial Networks (GANs), MySQL, Visual Studio Code (VS Code), Software Engineering, Artificial Intelligence (AI), Data Analytics, Java 8, JavaScript, Pandas, Scikit-learn, Node.js, Smart Contracts, Next.js, TypeScript, React Redux, System Design, Generative AI, Python, Machine Learning, API Integration, NoSQL, Data Science, Testing, SQL, Object-oriented Programming (OOP), APIs


2019 - 2022
  • Enhanced the OSS/BSS performance management software by developing new features using Java, multithreading, and Kafka. Employed Groovy, JUnit, and Cucumber for robust testing, increasing system efficiency and reliability by 20%.
  • Spearheaded the creation and implementation of an end-to-end (E2E) testing tool for the performance management application, reducing manual testing time from 2-2.5 weeks to just a few seconds and resulting in a 90% increase in efficiency.
  • Performed robust testing with Test-Driven Development (TDD) frameworks using Junit and Groovy and behavior-driven development (BDD) frameworks using Cucumber, ensuring the delivery of highly reliable software.
Technologies: Java 8, JavaScript, Bash, Python 3, Pandas, Scikit-learn, PostgreSQL, Apache Kafka, Java, Generative Adversarial Networks (GANs), Software Engineering, MySQL, Visual Studio Code (VS Code), Agile Sprints, Python, API Integration, Testing, SQL, Front-end, Object-oriented Programming (OOP), APIs, Groovy, Selenium, Cucumber, RHEL, Test-driven Development (TDD), Behavior-driven Development (BDD)

Passport V3

A lifestyle application based in Dubai that allows its users to access exclusive access to events, clubs, restaurants, etc., by sampling, finding, and booking on the app. PassportV3 is a combination of eCommerce, lifestyle, and Web3. It allows its users to be able to make bookings using both fiat and cryptocurrencies. They can use either of these currencies to make in-person payments using passport prepaid cards. It is a unique combination of fintech and social media lifestyle applications to serve the unique crowd of places like Dubai.


A behavioral finance platform aimed at blockchain traders to understand the role of their financial behavior and how others behave on the blockchain to make strategic decisions for their following trades.

Create Economy

A decentralized application that allows users to automatically create their cryptocurrency and receive them within their wallets in real time. I built this using React and advanced packages like react-spring for animations and Ethers.js for interacting with Ethereum or Binance smart chain RPC servers. Users can test the app using a test network or deploy their currency on the main network.

Anomaly Detection and Correction in 5G Core Networks

A DNN model can detect and correct anomalies (like DDoS attacks). It used a pre-trained latent space trained on expected network packets and could identify even the smallest modified packets and replace them with non-harmful packets or drop them.
2017 - 2018

Master's Degree in Computer Science

University College Dublin - Dublin


Simple Recurrent Neural Network with Keras



Build Better Generative Adversarial Networks



Build Basic Generative Adversarial Networks (GANs)



Introduction to XR: VR, AR, and MR Foundations



Design Thinking for the Greater Good: Innovation in the Social Sector

University of Virginia


Introduction to Augmented Reality and ARCore



Mathematics for Machine Learning: Multivariate Calculus

Imperial College London


Mathematics for Machine Learning: Linear Algebra

Imperial College London


Understanding Financial Markets

University of Geneva


Convolutional Neural Networks



Designing the Future of Work

The University of New South Wales (UNSW) Sydney


Structuring Machine Learning Projects



Neural Networks and Deep Learning



Improving Deep Neural Networks: Hyperparameter Tuning, Regularization and Optimization



React, Node.js, Pandas, D3.js, Scikit-learn, PyTorch, Keras, TensorFlow, Web3.js, React Redux, Stripe API, OpenZeppelin, Dask


Google Analytics, Jenkins, BigQuery, Mocha, Git, Amazon Elastic Container Service (Amazon ECS), Figma, Cucumber, Jira, Confluence, GitHub, Amazon EKS


Next.js, Jest, NestJS, Django, Cypress, JUnit, Express.js, Truffle, Hardhat, Tailwind CSS, Selenium, Spring 4


Data Science, Testing, Object-oriented Programming (OOP), Design Thinking, Behavior-driven Development (BDD), Test-driven Development (TDD)


JavaScript, Python 3, Solidity, TypeScript, Python, SQL, Java 8, Bash, Java, GraphQL, Groovy


MySQL, NoSQL, PostgreSQL, Amazon S3 (AWS S3), MongoDB


Visual Studio Code (VS Code), Amazon Web Services (AWS), Apache Kafka, Firebase, Docker, AWS Lambda


Smart Contracts, Machine Learning, API Integration, Front-end, CI/CD Pipelines, APIs, Software Engineering, Artificial Intelligence (AI), Data Analytics, Agile Sprints, System Design, CTO, Recurrent Neural Networks (RNNs), DCGAN, Convolutional Neural Networks (CNN), Generative Adversarial Networks (GANs), Ethers.js, Ethereum Smart Contracts, Generative AI, Web3, Subgraph, Architecture, Amazon RDS, Uniswap SDK, GitHub Runners, GitHub Actions, Machine Learning Operations (MLOps), RHEL, Office 365, Push Notifications

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