Senior QA Engineer (Cloud Communications)

TL;DR

Senior QA Engineer (QA Testing): Performing deep-dive analysis of complex multi-channel message flows and executing end-to-end validation for cloud communications platforms with an accent on API/backend flows and system-level testing. Focus on investigating root causes of delivery defects across various channels and contributing to automation and performance testing efforts.

Location: Remote, Office-based, or Hybrid. Medical insurance and sport card perks available for employees located in Bulgaria.

Company

A leading supplier in cloud communications delivering Messaging and Voice solutions to businesses in over 100 countries.

What you will do

• Analyze business requirements and technical specifications for web interfaces and backend to prevent production issues.
• Perform deep-dive analysis of multi-channel message flows (SMS, Telegram, Viber) using platform logs, webhook payloads, and event traces.
• Design and execute advanced end-to-end test strategies covering the full message lifecycle.
• Conduct performance testing using Locust to validate throughput, API response times, and system resilience.
• Support Playwright-based automation efforts and collaborate with engineers to improve coverage for critical UI flows.
• Maintain technical documentation and RCA reports for complex, hard-to-reproduce defects.

Requirements

• 5+ years of software testing experience.
• Strong expertise in web platform testing (UI + backend) and debugging distributed flows.
• Proficiency in REST API testing using Postman, curl, or similar tools.
• Experience validating webhook and callback flows and understanding channel-specific delivery logic.
• Experience working in Linux environments and reading server logs.
• Familiarity with Docker, Kubernetes, and Grafana or similar monitoring tools.

Nice to have

• Experience with Playwright or similar E2E frameworks.
• Hands-on experience with Locust, k6, or JMeter.
• Experience integrating tests into CI/CD pipelines.
• Understanding of event-driven architecture patterns and messaging provider APIs.

Culture & Benefits

• Flexible work format: choose between remote, office-based, or hybrid.
• Comprehensive medical insurance and sports card (for employees in Bulgaria).
• Access to mental health programs and supportive mentorship.
• Free educational events, courses, and English classes with native speakers.
• Friendly atmosphere with corporate gifts and performance bonuses.