Senior QA Engineer

About MMDSmart: Since 2007, MMDSmart has been an industry-leading global pioneer in cloud communications, delivering game-changing smart messaging, B2B interaction channels, and enterprise voice solutions to businesses across more than 100 countries. Our platform empowers international brands to connect seamlessly with their global audiences through highly scalable, real-time message routing layers. Built on a culture that celebrates individual potential, innovation, and continuous personal growth, MMDSmart nurtures a virtual-first team of experts focused on transforming complex legacy communication workflows into elegant, cloud-delivered experiences.

Position Overview

We are seeking a highly technical, systems-minded Senior QA Engineer with a strong software verification background to join our core R&D team. In this multi-faceted role, you will serve as a principal System Investigator, taking ownership of end-to-end and system-level validation across our communication infrastructure. Moving far beyond trivial manual interface testing, you will perform deep-dive root cause analyses on distributed, multi-channel message flows (spanning SMS, Telegram, Viber, and APIs) utilizing backend log streams, server traces, and webhook payloads. Additionally, you will bridge the gap into automation by expanding our Playwright test suites, configuring load parameters with Locust, and embedding quality guardrails directly inside our CI/CD pipelines.

Key Responsibilities

• System Investigation & Log Analysis: Execute deep diagnostics on complex, distributed message flows using backend server logs, webhook payloads, and event traces across Linux environments.
• End-to-End Strategy Design: Architect and execute comprehensive test plans tracking the complete message lifecycle—from admin web actions through gateway APIs down to asynchronous carrier delivery confirmations.
• API & Webhook Verification: Stress-test, validate, and document backend transaction layer behaviors and RESTful endpoints utilizing advanced Postman or curl configurations.
• Performance & Concurrency Testing: Lead performance benchmarking efforts under heavy concurrent channel load using Locust to track system throughput boundaries and latency spikes.
• Automation Framework Support: Partner with core SDET specialists to scale and maintain our existing Playwright end-to-end automation modules built on JavaScript/TypeScript or Python.
• Agile Quality Advocacy: Participate actively in architectural system designs and product reviews, championing codebase testability, monitoring hooks, and overall platform stability.
• RCA Documentation Management: Author robust technical specifications, regression logs, and Root Cause Analysis (RCA) records to capture hard-to-reproduce defects for long-term team learning.

Required Skills & Qualifications

• 5+ years of verified professional experience running software quality assurance, backend system testing, or technical defect analysis.
• Deep conceptual mastery of web platform dynamics, cross-system logic flows, and edge-case discovery within distributed systems.
• Hands-on operational experience validating asynchronous network behaviors, webhooks, callback patterns, and event-driven architectures.
• Strong backend diagnostic literacy, with practical experience analyzing server logs inside Linux, Docker, or Kubernetes environments.
• Familiarity with foundational API test automation concepts, script writing (via Python or JS/TS), and monitoring dashboards (such as **Grafana**).
• Location Context: 100% remote-first full-time operational framework restricted exclusively to qualified engineers permanently based in: **Poland, Serbia, Bulgaria, Czechia, or Georgia**.

Preferred Strategic Indicators (Nice to Have)

• Prior experience building test scripts natively within automated E2E testing environments like **Playwright, Cypress, or Selenium**.
• Hands-on profiling experience running performance automation tools such as Locust, k6, or JMeter.
• Familiarity with telecom infrastructure, messaging provider APIs, SMPP protocols, or SMS/chat platform delivery mechanics.

What We Offer

• The exceptional technical runway to directly influence and safeguard the real-time communications engine powering interactions across 100+ countries.
• Highly competitive regional salary compensation matrix matched accurately against your API and backend diagnostic depth.
• Profound work-from-home remote flexibility with options to operate 100% from home, utilize corporate offices, or deploy a hybrid schedule.
• Comprehensive health and wellness structures, including access to mental health programs, global corporate gift packages, and individual bonuses.
• Specialized regional perks for Bulgaria-based team nodes, including expanded medical insurance coverage and multi-sport cards.
• Continuous personal development paths, providing free technology courses, internal training tracks, and localized English classes with native speakers.