Long-running, mission-critical enterprise system used by restaurant chains across the US and Canada. The platform consisted of multiple tightly coupled subsystems covering operations, billing, reporting, integrations, and back-office workflows, with high availability and performance requirements.

Strategic transformation program to migrate a monolithic legacy platform to a modern, service-oriented architecture with a web-based frontend, while continuing to support existing customers and live operations.

Supported and evolved a collaboration platform used by Donnelley Financial Solutions (DFIN) customers to produce disclosure reports. I implemented new API endpoints, improved reliability and performance in a high-load enterprise environment, and contributed to refactoring legacy areas to reduce operational risk.

I also helped strengthen the delivery process by migrating CI/CD from TFS to Azure DevOps, introducing build validation and automated testing practices to improve release confidence and reduce manual effort.

Worked with SharePoint at enterprise scale to support DFIN-related reporting workflows. I investigated performance bottlenecks, improved stability under high concurrency, and helped troubleshoot issues affecting report generation and collaboration scenarios.

In close collaboration with the team, I contributed to hardening security and ensuring predictable behavior of reporting-related features in production environments.

Led the migration of the engineering toolchain from Perforce to Azure DevOps to improve delivery speed, traceability, and collaboration between development and QA. I designed the target workflow (Git repos, branching strategy, PR policies, and release process), rebuilt CI/CD pipelines, and introduced standardized quality gates (build validation, automated tests, and code review checks). As a result, the team reduced manual release activities, improved change visibility across environments, and accelerated feedback loops for QA through repeatable deployments and consistent build artifacts.

Worked closely with the ERP team to implement and integrate SAP S/4HANA (SAP HANA-based ERP) into the company’s ecosystem. I extended and improved custom modules on the application side and delivered integration components to synchronize critical business data and processes between ERP and internal services.

Key contributions included defining integration contracts with stakeholders (data mapping and validation rules), implementing reliable data exchange flows (including error handling and retries), and supporting end-to-end delivery together with QA (integration testing, regression testing, and production cutover support). This improved system interoperability, reduced manual operations, and increased transparency of business transactions across teams.

Enhanced and extended an automated warehouse system used to coordinate picking/packing flows. I improved core modules responsible for warehouse operations, stability, and throughput, and helped implement monitoring and control for warehouse robots and conveyor lines to ensure reliable execution of workflows and fast incident response.

Built the Kyiv delivery team to support the German headquarters. I defined the team structure and roles, participated in recruitment and interviewing for both developers and QA engineers, and established onboarding and ways of working (engineering standards, code review culture, and QA collaboration). This enabled predictable delivery capacity locally and improved communication and delivery flow between Kyiv and the main office.

Implemented and supported data exchange between accounting subsystems and multiple e-commerce websites. I designed and maintained integration flows (data mapping, validation, and reconciliation) and coordinated changes with the teams responsible for each site to ensure consistent contracts, reliable releases, and minimal downtime during updates.

Developed a crawler to parse e-commerce websites and generate actionable data-quality reports. The solution collected and validated product availability, price accuracy, and content completeness (titles, descriptions, images, attributes), then produced consolidated reports to highlight discrepancies and missing information for business and content teams.

Led the rollout of 1C:Enterprise 8.3 as a company-wide ERP backbone, automating warehouse operations and standardizing core processes across all offices. I also implemented a retail accounting system based on 1C for the store network to ensure consistent inventory, pricing, and sales reporting.

This initiative provided a major operational boost: it reduced manual work, improved data consistency, and enabled reliable, scalable expansion of the retail network. As a result, the company accelerated growth and strengthened its position to become a key player in the Ukrainian market.

Transformed the internal IT function to support rapid company growth. I restructured teams (service desk, infrastructure, business analysis, 1C, mobile, and web), introduced clearer ownership and SLAs, and improved cross-team delivery by aligning priorities with business stakeholders. This increased throughput, reduced operational bottlenecks, and improved reliability of day-to-day IT services.

Implemented Active Directory-based enterprise management to centralize identity, access control, and workstation/server policies. I standardized account provisioning, improved security through group-based access and GPOs, and enabled scalable onboarding/offboarding workflows across offices, warehouses, and retail locations.

Led the rollout of corporate email on Microsoft Exchange, standardizing mailboxes, distribution lists, and access policies across the company. Coordinated the migration plan, user onboarding, and operational support to ensure a smooth transition and improved collaboration and reliability of corporate communications.

Planned and executed the migration of key services and data processing/storage workloads to cloud environments (private cloud and Google). I improved scalability and availability, established backup and disaster recovery practices, and optimized operating costs by consolidating infrastructure components and automating provisioning where possible.

Designed and implemented a VMware-based virtualization platform to standardize server workloads, improve resilience, and speed up provisioning. I introduced virtualization best practices, consolidated physical servers, and improved monitoring and capacity planning to support stable 24/7 operations.

Integrated and customized a 1C ERP subsystem across the enterprise as the sole developer, delivering end-to-end automation for both wholesale and retail operations.

I covered the full lifecycle: requirements clarification with business users, configuration and customization, data exchange and reporting, performance tuning, and production support. The solution optimized day-to-day workflows for managers, warehouse teams, and back-office functions, reduced manual operations, and improved data consistency across departments.

Developed a wholesale sales mobile application for iOS using early Swift versions. The app supported day-to-day work for sales managers: product catalog access, price/availability checks, customer and order workflows, and synchronized data with the back-office systems to keep business-critical information consistent across channels.

Developed a wholesale sales application for Android to support field and office sales workflows. The solution provided fast access to product data, customer information, and order creation, and integrated with internal services to ensure reliable synchronization and reporting.

Developed an Android retail sales application in Kotlin to support in-store operations. The app streamlined day-to-day workflows such as product lookup, pricing and availability checks, and sales/order capture, and integrated with internal back-office services to keep inventory and sales data consistent across stores.

Developed and maintained a set of marketing websites for the company and separate product groups to support online promotion. The sites were used to publish product information and marketing content, run advertising campaigns, and improve organic search visibility through structured content, landing pages, and SEO-friendly site architecture.

Developed a series of SPA websites for marketing events and product campaigns. The sites included landing pages and attendee registration flows (forms, validation, and basic analytics), and integrated with internal services to collect registrations and provide operational reporting for event coordinators.

Developed an internal API layer to enable reliable integration between back-office systems, company websites, and mobile applications. I designed stable integration contracts, implemented core endpoints for product/catalog, pricing, and order workflows, and ensured consistent data synchronization across channels for both wholesale and retail use cases.