Senior QA Engineer
Freedx
Role Overview
We are looking for a Senior QA Engineer to ensure the quality, reliability, and accuracy of trading and related products for a centralized crypto exchange.
This role requires strong technical knowledge and an understanding of complex financial systems. You will test core trading operations, real-time data streams, financial calculations, APIs, system integrations, analytics, and user-facing dashboards.
You will work closely with Product Managers and Engineering teams throughout the full development lifecycle, from requirement analysis and test planning to release validation and production incident investigation.
The ideal candidate understands how trading systems behave under normal, edge-case, and failure scenarios and can identify risks related to incorrect calculations, delayed data, system synchronization, balance inconsistencies, and order execution.
Responsibilities
- Own the QA process for trading and analytics products.
- Review product requirements and identify missing scenarios, risks, and technical dependencies.
- Test order creation, execution, cancellation, rejection, and order status transitions.
- Test system integrity, real-time market data, WebSocket streams, and synchronization between services.
- Validate PnL, margin, liquidation, fees, balances, funding, and risk-control calculations.
- Test trading dashboards, system analytics, reports, and data consistency.
- Perform functional, integration, API, UI, regression, and end-to-end testing.
- Create test plans, test cases, checklists, test data, and regression suites.
- Verify that product delivery meets functional, technical, and quality standards.
- Test negative scenarios, edge cases, service failures, and recovery flows.
- Investigate production issues, reproduce defects, analyze logs, and support incident reviews.
- Work closely with Product Managers, developers, DevOps, data, and support teams.
- Improve release validation, defect prevention, QA processes, and test coverage.
- Cross device product support
Requirements
- 4+ years of QA experience.
- Experience with crypto or FX exchanges, brokerage, fintech, or trading platforms.
- Strong understanding of order books, order types, liquidity, margin, PnL, fees, and liquidation.
- Experience testing APIs, WebSockets, databases, analytics dashboards, and complex data flows.
- Experience with functional, integration, regression, and end-to-end testing.
- Ability to validate financial calculations and complex business logic.
- Ability to analyze system behavior across multiple connected services.
- Strong analytical, technical, and communication skills.
- High attention to detail and a structured approach to problem-solving.
- Experience with test automation is a plus.
- Knowledge of authentication, payments, deposits, withdrawals, and balance operations is a plus.
- English level B2
Technical Skills and Tools
- Strong experience testing REST APIs using Postman or similar tools.
- Experience working with Swagger/OpenAPI documentation.
- Experience testing WebSocket connections and streamed data.
- Good knowledge of JSON, authentication methods, request headers, status codes, and API error handling.
- Experience using browser developer tools for frontend and network debugging.
- Experience with log monitoring and analysis tools such as Kibana, Grafana, Datadog, or similar.
- Experience with performance-testing tools such as JMeter, k6, or similar.
- Experience with test management and issue-tracking tools such as Jira, TestRail, Zephyr, or similar.
- Understanding of microservice architecture, message queues, and asynchronous system communication.
- Experience with Kafka, RabbitMQ, or similar technologies is a plus.
- Ability to write SQL queries and validate data directly in databases is a plus.
- Experience with automation tools such as Playwright, Cypress, Selenium, or similar is a plus.
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