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Blockchain Logo Blockchain · IT - Software Development

Software Engineer, Fraud

United Kingdom, London · Job Posted December 06, 2025
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Job Description

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. Blockchain.com is the world's leading software platform for digital assets. Offering the largest production blockchain platform in the world, we share the passion to code, create, and ultimately build an open, accessible and fair financial future, one piece of software at a time. We are looking for software engineers from a variety of technical backgrounds with a proven track record in building scalable, reliable and performant systems. You will play a critical role in building financial and crypto-native products, services and APIs. As a Senior Back-End Engineer you should lead by example - driving the technical discussions, influencing the approach and making a positive impact on the team's development by advocating the best engineering practices.

Job Responsibility

  • You will be part of the Brokerage - Orders team who enable buy, sell and swap of crypto
  • Develop and integrate APIs from new and existing services, to our various product applications.
  • Become a key member of a dedicated engineering team committed to rapidly shipping, and iterating on products that directly impact millions of users
  • Advocate best practices, code quality, test coverage and drive technical discussions
  • Optimise existing systems for scalability, extensibility and performance whilst building out reusable, modular code for use across Blockchain’s products
  • Ensure security is at the forefront of everything you do, employing advanced encryption schemes to secure user and company data
  • Work within interdisciplinary teams to continually deliver the highest quality software to our users

Requirements

  • You know at least one programming language in depth
  • You have at least 7 years experience building and shipping highly-available, fault tolerant, production ready distributed backend systems
  • You have experience in any JVM based languages (such as Java, Kotlin, Scala) and are confident in your ability to build, debug and ship microservices
  • You are customer focused and continuously suggest how the backend can provide the best Customer Experience
  • You pride yourself on consistent high levels of test coverage, strong technical documentation and effective monitoring

Nice to have

  • Preferably exposure to technologies such as Kafka, PostgreSQL, Redis
  • Have a basic understanding of reactive systems using CQRS and event sourcing. A bonus would be experience using Akka.
  • A passion for crypto and the transformations it enables

What we offer

  • Full-time salary based on experience and meaningful equity in an industry-leading company
  • Hybrid model working from home & awesome office location in the heart of London
  • Work from Anywhere Policy: You can work remotely from anywhere in the world for up to 20 days per year.
  • 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
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