Software Development Engineer in Test

Blockchain.com is connecting the world to the future of finance. As the most trusted and fastest-growing global crypto company, it helps millions of people worldwide safely access cryptocurrency. Since its inception in 2011, Blockchain.com has earned the trust of over 90 million wallet holders and more than 40 million verified users, facilitating over $1 trillion in crypto transactions.

We’re looking for a Software Development Engineer in Test (SDET) to join our Institutional team in London. At Blockchain.com, we thrive in a high-performance culture defined by fearlessness, ownership, and hyper-productivity. As an SDET, you will play a critical role in ensuring the quality, reliability, and performance of our trading and financial systems.

WHAT YOU WILL DO

• Design and build automated test frameworks and tools for low-latency, high-throughput trading services.
• Develop, maintain advocate test suites across the full product lifecycle:
• Unit testing
• Integration testing (local and end-to-end) Performance and load testing
• Failure recovery testing
• Collaborate with software engineers to embed quality from the ground up in OMS, exchange gateways, risk management systems, and settlement services. Monitor, analyze, and improve system reliability, scalability, and performance through continuous testing.
• Ensure security-first testing practices, validating encryption schemes and protecting user and company data.
• Work closely with cross-functional teams to provide feedback, drive improvements, and raise the bar for engineering excellence.

WHAT YOU WILL NEED

• Innate curiosity and a strong passion for quality engineering.
• Professional experience as an SDET, QA Automation Engineer, or Software Engineer with a focus on testing.
• Strong experience with Python (test automation, scripting, or backend validation).
• Familiarity with SQL for data validation.
• Experience in one or more of the following is a strong plus:
• Distributed systems testing
• Kubernetes-based test environments
• Messaging technologies (Jetstream NATS, Redis, etc.)
• Load/performance testing tools (Locust, JMeter, Gatling, etc.)
• A pragmatic, hands-on approach to solving complex problems.
• Solid understanding of algorithms, data structures, databases, and distributed systems.
• Passion for building automation-first testing cultures, minimizing manual work wherever possible.

COMPENSATION & PERKS

• Full-time salary based on experience and meaningful equity in an industry-leading company
• This is a hybrid role based in our London office, with a mandatory in-office presence four days per week.
• Work from Anywhere Policy: You can work remotely from anywhere in the world for up to 20 days per year.
• ClassPass
• Unlimited vacation policy; work hard and take time when you need it
• Apple equipment
• The opportunity to be a key player and build your career at a rapidly expanding, global technology company in an emerging field
• Flexible work culture