Dima Green

Backend-focused QA Engineer

Israel / Open to Remote Email: contact@owefl.com
Backend QA Distributed Systems Payments API Testing
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Summary

Backend-focused QA Engineer with 8+ years of experience testing distributed, transaction-heavy systems, including e-commerce platforms, payment integrations, POS infrastructure, and ERP workflows.

Strong focus on business logic validation, transactional consistency, and edge cases around concurrency, retries, and multi-system behavior.

Professional Experience

Independent Projects & Technical Research (2024 - Present)

  • Designed and tested API-driven multi-tenant systems with isolated configuration handling.
  • Built Python-based validation tools for backend logic and integration testing.
  • Tested Redis caching behavior, retry mechanisms, and timeout handling in backend flows.
  • Tested WebSocket-based real-time interaction and state synchronization flows.

Senior QA Engineer (2019 - 2024)

  • Tested ERP system and e-commerce engine with focus on backend business logic, transactional workflows, and system integrations.
  • Validated payment integrations and transactional consistency in business-critical scenarios.
  • Tested POS backend systems deployed across 2,000+ devices in a distributed environment.
  • Validated SSO integration with Microsoft Entra ID across web and mobile platforms, including session handling and access control.
  • Tested promo-code and discount systems with focus on concurrency and duplicate usage protection.
  • Validated delivery service backend logic, including order lifecycle, state transitions, and failure scenarios.
  • Investigated production incidents using Kibana logs and SQL queries.
  • Participated in release process using GitLab CI/CD, validating builds and environments generated via pipelines.

QA Engineer (2015 - 2019)

  • Web and mobile functional testing with strong backend validation focus.
  • API testing and SQL-based data verification.
  • Release cycles, defect triage, test preparation, execution, and validation.

Selected Technical Projects

  • Designed multi-tenant backend systems with encrypted configuration handling.
  • Implemented JWT authentication with token blacklist validation and role-based access control.
  • Developed API validation suites using pytest and asynchronous HTTP clients.
  • Built containerized document-processing workflows with Python and Docker/Podman.