Senior Software Engineer, Quality Engineering (SDET)

As a Senior Software Engineer, Quality Engineering (SDET) at Startale, you will own the engineering foundations of quality across a next-generation decentralized exchange built in partnership with SBI Group. The platform features a fully on-chain order book with a custom state transition function and consensus layer, designed for low-latency, high-throughput trading of Japanese equities. Rather than writing automated tests, you will design and build the testing architecture, automation frameworks, developer tooling, CI/CD integrations, and AI-powered quality systems that enable the entire engineering organization to ship quickly and confidently.

What you'll do

• Design, build, and evolve the company's quality engineering platform, defining testing architecture across unit, integration, contract, API, and end-to-end testing.
• Build and maintain reusable testing frameworks, shared libraries, fixtures, and developer tooling that improve developer experience around testing and quality engineering.
• Design reliable test data generation and management strategies that enable deterministic and repeatable testing.
• Design and implement AI-assisted quality engineering workflows throughout the software development lifecycle, building systems that leverage LLMs for automated test generation, test maintenance, failure analysis, root cause identification, and regression detection.
• Build comprehensive automated test suites covering APIs, backend services, frontend applications, and blockchain interactions, integrated into CI/CD pipelines with fast feedback cycles.
• Optimize test execution through parallelization, intelligent test selection, caching, and infrastructure improvements.
• Validate the correctness of trading flows, order matching, execution paths, routing logic, fee calculations, and settlement, ensuring consistency between backend services, blockchain state, and frontend behavior.
• Design robust regression suites protecting the platform's critical trading functionality under real-world market conditions and edge cases.
• Build and maintain containerized testing environments using Docker and modern infrastructure tooling.
• Develop automated load, stress, endurance, and resilience testing for high-throughput trading services, validating system behavior during degraded conditions, network failures, timeouts, and infrastructure outages.
• Work closely with Backend, Frontend, Blockchain, DevOps, and Product teams to improve overall system quality and participate in architecture discussions to ensure systems are designed for testability and reliability.
• Mentor engineers on automated testing, testing architecture, and quality engineering principles.

What you bring

• 3+ years in SDET, Quality Engineering, or software engineering with a testing focus.
• Experience testing an exchange or trading system, including order types, matching, and trading flows.
• Demonstrated ability to build test systems and automation frameworks, not just test cases, with hands-on experience in CI/CD and Docker.
• Proficiency in API testing across REST, JSON-RPC, and WebSocket.
• Regular daily use of AI for test design, code generation, and failure analysis.
• Proficiency in JavaScript or TypeScript, or strong capability in other languages.
• Self-directed approach, comfortable working independently from the start.

Nice to have

• Experience building internal developer-productivity or quality-engineering platforms.
• Experience designing testing architecture for complex distributed systems covering API, integration, contract, and end-to-end strategies.
• Experience designing and implementing performance, load, and reliability testing using tools such as k6, Artillery, Gatling, or Locust.
• Strong understanding of observability and production debugging with tools like OpenTelemetry, Prometheus, Grafana, or Datadog.
• Experience debugging distributed systems across frontend, backend, APIs, databases, and infrastructure.
• Experience designing and managing reliable test data and testing environments.
• Experience testing complex transactional, financial, or high-throughput systems.
• Familiarity with blockchain fundamentals, smart contracts, and on-chain flows, including order books, AMMs, liquidity pools, routing, and execution.
• Experience with Kubernetes and cloud-native infrastructure.

About Startale

Startale is building a next-generation decentralized exchange in partnership with SBI Group, creating secure, transparent, and high-performance trading infrastructure for Japanese equities on-chain.