Oleh – Node.js, AWS, Next.js

A rental marketplace for neighbors to cooperate and lend/borrow resources. The platform aims to cultivate a culture of neighborhood collaboration, where lending and borrowing foster meaningful relationships and community solidarity.

• Led the team, communicated with the Project Owner and conducted code reviews
• Set up the project with Next.js, Nest.js, MongoDB, and AWS from scratch
• Implemented authentication and authorization logic with AWS Cognito
• Built UI and business logic of the application to provide users with content feeds, geo-fenced communities, efficient search with OpenSearch and real-time messaging with Socket.io
• Configured the deployment of the application to Vercel and AWS

A comprehensive platform designed to streamline merchant application processes, centralize documentation and simplify onboarding management for businesses. It helps businesses manage and optimize multiple MIDs, route transactions based on different criteria, track transactions across all MIDs and get insights into success rates and ROI, and integrate with Shopify and key payment gateways for a smooth eCommerce experience.

• Built Shopify integration feature with the support to connect to Shopify, manage data, and inject scripts for streamlined functionality
• Developed and published a custom checkout page that redirects users from Shopify's cart to TagadaPay's payment page, enabling secure and efficient payment processing and tracking
• Refactored the critical modules of the web application to optimize performance by adjusting caching and improve maintainability
• Optimized database schema to improve the structure and efficiency of data retrieval and management and to support new integrations more smoothly
• Extended the platform's API to support new platform capabilities such as generic third-party integrations
• Actively participated in the architecture and design of schema structures for the project

Web application for oil and gas production analysis and forecast. It helps track daily production rates, find and investigate production losses, calculate multiple indicators, allocate production issues, visualize vast amounts of data, and provide unique insights to oil engineers.

• Created a high-performant web application that smoothly works with large amounts of data and makes calculations on the fly
• Implemented custom charts with SVG and Canvas to support visualization of large amounts of data
• Designed and built API with architectural solutions to support large data amounts and keep the codebase scalable
• Set up complex infrastructure on top of AWS and Kubernetes with many application instances to handle incoming traffic
• Covered crucial business logic with unit tests using Jest

A solution for enterprise-level organizations to effectively manage insurance compliance across their internal operations, contractors, and partners. It provides tools to automate document collection, tracking, and verification, and allows for building an accurate and efficient risk-management program.

• Built a web application from scratch using React, with an advanced UI on top of Ant Design and optimized management of the async state
• Developed core business logic of the platform, including authentication and authorization, document management, reminders, and in-app messaging, supported by Express.js and MongoDB
• Covered critical logic with E2E tests using Cypress to improve the platform's stability
• Integrated New Relic and Sentry for monitoring and error tracking to keep the platform's usability at a high level
• Configured application infrastructure with Terraform and AWS, streamlined the deployment process with CI/CD pipelines

Product for internal business operations management: customers and contracts management, time tracking and financial reporting, recruitment, and sales tools. The web application is tailored for business needs and provides on-premise integration to clients. The product development started as an internal company solution and turned into a product used by numerous agencies in Europe.

• Implemented front-end application
• Performed API design, development, and documentation
• Covered application test with unit and end-to-end tests using Jest and Cypress

This application collects financial news data from different sources, analyses trending data, and helps find useful insights.

• Made implementation of UI/UX based on the Figma design
• Implemented static Blog pages with the support for filtering and developer API support
• Covered critical business logic with unit tests using Jest, ensuring application’s stability
• Streamlined the deployment of the application to Goole Cloud by introducing CI/CD pipeline