Senior .NET Developer

PYPL-BONE (Braintree + SAP Business One integration)

About the Project

Payment Processing system — full-scale multi-process .NET integration of Braintree (PayPal) with SAP Business One ERP. Started as a POC and evolved into a production distributed payment platform. Included SAP B1 desktop add-on, Web-Client browser application, backend APIs/services, async messaging layer, and customer-facing payment UI. Architecture included three deployable services: Web App, B1 Agent, and CronJob. The solution supported secure payment workflows, ERP synchronization, and background processing for operational and settlement-related flows.

• Fintech
• Accounting

Responsibilities

-Acted as Deputy Team Lead and key backend/full-stack .NET engineer on SAP B1 + Braintree payment platform; -Built and maintained SAP Business One add-on and backend APIs for end-to-end payment workflows inside SAP B1 Client; -Designed RabbitMQ-based integration between Web Service, CronJob, and B1 Agent to isolate SAP DI API and keep web layer responsive; -Owned payment orchestration: auth/capture/refund/void, 3DS (CIT/MIT/3RI), CVV, vaulting/tokenization, and Braintree GraphQL flows; -Implemented idempotency, reconciliation, and safe retry patterns for reliable async processing; -Built Settlement Dashboard search with cursor pagination, deduplication, and bulk enrichment across SAP HANA/MSSQL; supported .NET 8 modernization and tests.

ConstructConnect (Software & Hi-Tech — Construction technology platform for preconstruction and bidding workflows)

About the Project

NextGen platform initiative focused on designing and developing shared backend and security capabilities by augmenting customer development teams. Supported a large enterprise ecosystem covering 20+ products with user lifecycle, license provisioning, registration, and authentication flows. The project emphasized scalable platform architecture, secure integrations, operational stability, and performance improvements. Worked in a distributed environment using .NET, REST APIs, messaging, cloud, and identity platforms to support ongoing product evolution.

• Construction
• Product Management

Responsibilities

- Acted as a backend engineer and development stream lead within a large-scale program delivering platform and security functionality for 20+ products; - Designed and implemented REST APIs for user provisioning, registration, authentication, and license management; - Integrated Auth0, JWT-based security, API management, and cloud identity components into existing services; - Improved performance and stability of existing products through refactoring, validation, messaging, caching, and SQL optimization; - Contributed to product support, bug fixing, estimation, testing, CI/CD, and technical communication; - Ensured code quality using testing tools (NUnit/xUnit) and version control; - Participated in Agile ceremonies and production support.

Donor Agents

About the Project

Digital charity platform for Ukrainian blood donors. Included mobile application for individual donors and admin panel for blood agents. Focused on donor registration, management, and support of administrative workflows. Built as a web-based solution with separate user-facing and admin functionality.

• Non-profit

Responsibilities

- Contributed to full-stack development using C#, .NET 5, ASP.NET Web API, MVC, Entity Framework 6, and PostgreSQL; - Implemented and supported API features for donor and admin workflows; - Designed simple modular backend components to improve maintainability and feature delivery; - Performed bug fixing, maintenance, and database migrations, ensuring application stability and schema consistency; - Supported frontend implementation with React, HTML, CSS, and Bootstrap; - Improved code quality, basic security, and development practices using SonarQube, Swagger, GitLab, and GitHub; - Worked in Agile environment with task tracking and team collaboration in Jira.

SPA for Car Price Aggregation and Comparison

About the Project

Internal web platform for car price aggregation and comparison. Included data collection/parsing, storage, and search/comparison UI. Focused on collecting vehicle prices from external sources and comparing offers from foreign markets. Helped analyze imported car prices with customs clearance considerations against AUTO.RIA market prices. Covered the full flow from data ingestion and persistence to search and comparison features for end users.

• Automotive

Responsibilities

- Contributed to full-stack development using C#, .NET 5, ASP.NET Web API, Entity Framework, PostgreSQL, HTML, CSS, and JavaScript; - Designed and implemented new features for data collection, persistence, and search/comparison workflows; - Built Web API endpoints and backend logic for processing and exposing vehicle pricing data; - Performed bug fixing, iterative improvements, and application support; - Applied modular structure, basic automated tests, and Git-based development practices; - Supported UI development for search and comparison functionality.