Senior Apache Cassandra Engineer

About the Role

We are seeking an experienced Senior Apache Cassandra Database Engineer to join our Business Platform team supporting critical Financial Crime and Payments systems.

You will play a key role in designing, building, and operationalising a high-performance Apache Cassandra platform that underpins a real-time payment capture and replay solution for fraud detection.

This role requires deep technical expertise in Apache Cassandra, NoSQL data modelling, performance optimisation, and production support within a highly regulated financial services environment.

You will work closely with application, infrastructure, middleware, and security teams to deliver a resilient, scalable, and secure data platform.

Key Responsibilities

• Design and implement Apache Cassandra clusters, keyspaces, replication strategies, and partitioning models.
• Develop scalable Cassandra data models aligned with application query patterns.
• Optimise read/write performance through appropriate consistency levels, compaction strategies, and JVM tuning.
• Design highly available, fault-tolerant Cassandra cluster architectures.
• Perform cluster administration including node additions, decommissioning, repairs, backups, upgrades, and disaster recovery.
• Monitor database health and performance using tools such as Prometheus, Grafana, DataStax OpsCenter, or equivalent.
• Support application teams with CQL query optimisation and Cassandra best practices.
• Collaborate with Actimize, IBM MQ/IIB, middleware, infrastructure, and security teams to ensure seamless platform integration.
• Implement database security including encryption at rest, encryption in transit, authentication, and RBAC.
• Produce technical documentation including solution designs, operational runbooks, support procedures, and knowledge transfer documentation.
• Deliver solutions in line with enterprise governance, regulatory standards, and change management processes.

Required Skills & Experience

• 4–9 years of hands-on experience administering and engineering Apache Cassandra in production environments.
• Strong expertise in Cassandra architecture, keyspace design, replication strategies, partition key design, and data modelling.
• Excellent understanding of Cassandra internals including SSTables, Memtables, Commit Log, Gossip Protocol, Tombstones, and Compaction.
• Strong experience with CQL development and performance tuning.
• Hands-on experience managing Cassandra clusters including repairs, scaling, backups, disaster recovery, and capacity planning.
• Strong Linux administration skills.
• Scripting experience using Bash and/or Python.
• Experience with monitoring tools such as Prometheus, Grafana, or DataStax OpsCenter.
• Good understanding of database security, encryption, authentication, and RBAC.
• Experience working within Agile delivery environments.
• Experience with NICE Actimize.
• IBM MQ, IBM Integration Bus (IIB), or Apache Kafka.
• Oracle PL/SQL.
• DataStax Enterprise.
• Cassandra/DataStax certifications.
• AWS Keyspaces or Azure Managed Instance for Apache Cassandra.
• Previous experience in Banking, Financial Services, Payments, or Financial Crime platforms.

What You'll Be Working On

• Real-time payment transaction processing platform.
• Fraud detection and financial crime systems.
• High-volume NoSQL data platform.
• Performance-critical, highly available Cassandra infrastructure.
• Cross-functional collaboration with architecture, middleware, infrastructure, security, and application teams.

Ideal Candidate

You are a highly skilled Cassandra specialist who enjoys solving complex performance and scalability challenges.

You have strong ownership, can work independently, and are comfortable designing enterprise-scale NoSQL solutions while collaborating across multiple technology teams in a regulated financial services environment.