Senior Database Engineer

We are seeking an experienced Senior NoSQL Database Administrator to take end-to-end operational ownership of enterprise-grade ClickHouse and MongoDB platforms supporting business-critical, high-volume workloads across AWS, Microsoft Azure, and on-premises environments.Deep, hands-on production expertise in ClickHouse and MongoDB is mandatory for this role. The successful candidate will own database architecture and design, performance engineering, high availability and disaster recovery, backup and restore, security and compliance, capacity planning, upgrades and migrations, automation, observability, and 24x7 production support.Educational Qualification and Professional CertificationsBachelor's Degree in Computer Science, Information Technology, Engineering, or a related technical field.MongoDB Certified DBA (Associate or Professional).ClickHouse professional certification or equivalent demonstrable vendor training.ITIL Foundation or equivalent IT service management certification.Required Professional Experience8+ years of overall IT and database administration experience, with the majority spent on NoSQL database technologies.5+ years of hands-on production experience administering MongoDB, including replica sets, sharded clusters, and MongoDB Atlas or Ops Manager.3+ years of hands-on production experience administering ClickHouse, including cluster design, MergeTree engine family, replication, and distributed tables.Proven experience operating large-scale (multi-terabyte), high-availability, business-critical database estates with demanding SLAs.Demonstrated experience delivering 24x7 production support and participating in an on-call rotation for tier-1 platforms.Hands-on experience running databases across AWS, Microsoft Azure, and on-premises or hybrid infrastructure.8+ years of overall IT and database administration experience, with the majority spent on NoSQL database technologies.5+ years of hands-on production experience administering MongoDB, including replica sets, sharded clusters, and MongoDB Atlas or Ops Manager.3+ years of hands-on production experience administering ClickHouse, including cluster design, MergeTree engine family, replication, and distributed tables.Proven experience operating large-scale (multi-terabyte), high-availability, business-critical database estates with demanding SLAs.Demonstrated experience delivering 24x7 production support and participating in an on-call rotation for tier-1 platforms.Hands-on experience running databases across AWS, Microsoft Azure, and on-premises or hybrid infrastructure.Key Responsibilities:Database Administration & OperationsOwn day-to-day administration, monitoring, and operational health of all production and non-production ClickHouse and MongoDB environments.Perform installations, configuration, patching, version upgrades, and decommissioning across cloud and on-premises estates.Manage user provisioning, roles, privileges, quotas, and access reviews in line with least-privilege principles.Maintain accurate platform documentation, runbooks, standard operating procedures, and configuration baselines.Architecture & DesignDesign and size ClickHouse clusters, including sharding and replication topology, MergeTree engine selection, partitioning, primary key and ordering key strategy, TTL, and materialised views.Design MongoDB replica sets and sharded clusters, including shard key selection, indexing strategy, schema design guidance, and read/write concern configuration.Define database standards, naming conventions, and reference architectures; review application data models before production release.Deliver capacity planning and growth forecasting for storage, memory, compute, and I/O.Performance Engineering & OptimisationProactively identify and resolve performance bottlenecks through query profiling, execution plan analysis, index tuning, and resource contention analysis.Tune ClickHouse query performance, merge behaviour, compression codecs, projections, skip indexes, and resource quotas for high-ingest analytical workloads.Tune MongoDB performance using the aggregation framework, index optimisation, WiredTiger cache sizing, and connection pool management.Establish and track performance baselines, and report on SLA and SLO adherence.High Availability, Backup & Disaster RecoveryImplement and maintain high-availability topologies, replication, failover automation, and multi-region or multi-AZ resilience.Own backup and recovery strategy, including scheduling, retention, encryption, offsite copies, and point-in-time recovery.Plan and execute regular restore drills and disaster recovery tests; validate RPO and RTO objectives and remediate gaps.Security & ComplianceImplement database hardening, encryption at rest and in transit, authentication and authorisation, auditing, and key management.Support internal and external audits, vulnerability remediation, and compliance with applicable regulatory and data-protection requirements.