Software Development Engineer in Test

Join us as an SDET at 3Commas, where you'll become a key part of the engineering team behind one of the most advanced crypto trading platforms in the world. You'll work side by side with developers, design test architecture, write production-grade code, and drive quality across real-time systems that power automated and manual trading. You'll take full ownership of testing as part of a shared engineering responsibility and contribute to products built with Ruby, TypeScript, and React.

Responsibilities:

• Develop and maintain automated tests: unit, integration, and end-to-end
• Design test strategies with a strong emphasis on automation from the ground up
• Test real-time and asynchronous systems: WebSocket, Kafka, REST APIs
• Integrate test coverage into the CI/CD pipeline (GitLab, Docker, Kubernetes)
• Monitor stability, detect flakiness, and identify performance regressions
• Investigate bugs deeply: analyze issues on the code, infra, or test level
• Write post-mortems for incidents and implement improvements accordingly
• Participate in load and chaos testing initiatives
• Work with observability tools (Grafana, Kibana, Sentry, Kubernetes logs)
• Collaborate closely with developers, DevOps, and product managers

Requirements:

• Understanding of the software development lifecycle and the QA role at each stage
• Familiarity with TDD, shift-left testing mindset, and the testing pyramid
• Strong prioritization skills in high-load environments
• Critical thinking and a proactive approach to improving QA/development workflows
• Experience with either Ruby or React
• Excellent communication skills (both online and in-person)
• Proficiency in English at B2 level or higher

Testing & Automation

• Proficient in TypeScript
• Hands-on experience with Playwright, Jest, or similar tools
• Experience with Page Object Model, mocking tools like msw or nock
• Solid skills in API testing: REST, WebSocket, optionally gRPC
• Deep knowledge of test design, test data isolation, and parallel execution

DevOps & Observability

• Confident with Docker and solid understanding of Kubernetes
• Comfortable working with logs, alerts, and dashboards (Grafana, Kibana, Sentry)

Nice to Have:

• Experience working with Ruby (Rails) or React.js in a production environmen
  
• Experience testing event-driven architectures (Kafka)
• Domain knowledge in crypto trading: order types, leverage, derivatives
• Familiarity with performance testing tools (e.g. k6)

What We Offer:

• Growth-Driven Role: Opportunity to transition from manual QA to automation using modern TypeScript-based frameworks, with mentorship and real hands-on practice
• Remote-First Culture: Work in a globally distributed team, with optional access to physical offices in Barcelona and Tallinn
• High Ownership: Play a key role in improving product quality and help design QA processes that scale across the engineering organization
• People-First Environment: Join a mission-driven company in the crypto domain with a culture rooted in trust, learning, and transparency