Location
London

Hours
Full Time

Salary
Negotiable

About the Role
Apple's Services Engineering organization (ASE) is seeking a deeply technical Distributed Systems Database Engineer to help architect the next generation of our massive-scale data platform. ASE Data Services operates Apache Cassandra and related coordination systems across Apple's datacenters worldwide, forming a foundational storage layer for iCloud and hundreds of millions of global users. As our fleet grows, we are evolving our platform to support true multi-tenancy, dense resource utilization, and highly predictable performance. You will design and build an intelligent, auto-balancing cluster control plane that dynamically optimizes our hardware footprint, moving comfortably between abstract capacity modelling and the realities of running distributed databases at scale.

The ASE Data Services team is building an automated, multi-tenant platform layer designed to maximize efficiency without compromising reliability. You will own the architecture for resource quota management, node-level capacity estimation, performance efficiencies, and dynamic cluster rebalancing algorithms across our fleet. Your work will include modeling CPU, memory, IOPS, and data-streaming requirements per node and building software that automatically redistributes data and workloads to optimize node count. Over time, the platform will leverage modern workload-scheduling and orchestration primitives to enforce boundaries, turning raw hardware into a highly efficient, self-healing, self-balancing multi-tenant utility.

Key responsibilities include designing and implementing an auto-balancing control plane that dynamically redistributes data and workloads, architecting streaming load optimization mechanisms to prevent production traffic degradation, developing robust multi-tenancy frameworks ensuring tenant isolation and safety, building algorithmic models for resource forecasting, maintaining quota management and rate limiting systems, implementing failure domain isolation strategies, and partnering closely with SRE, platform, and integration teams to deliver and operate the system with on-call-grade reliability.

Experience
- 7+ years in infrastructure engineering, systems programming, or distributed systems development
- Professional experience developing distributed systems including consensus protocols, replication strategies, or consistency models
- Experience profiling and modeling node-level resource usage (CPU, memory, I/O)
- Hands-on experience building auto-balancing systems, scheduling frameworks, or multi-dimensional resource allocation algorithms for large-scale distributed systems
- Familiarity with distributed database internals, especially LSM-tree architectures and streaming mechanics during node join/leave/move operations
- Experience running large-scale stateful workloads on orchestration platforms such as Kubernetes
- Experience implementing admission control, token/leaky-bucket algorithms, or distributed rate limiting in high-throughput environments
- Familiarity with Linux cgroups (v1/v2), eBPF, I/O schedulers, and network topologies governing resource isolation
- Experience transitioning large single-tenant legacy systems into modern shared-resource, auto-scaling architectures

About you
You have a bias toward experimentation, forming hypotheses, prototyping quickly, measuring honestly, and letting data guide architectural decisions. You possess deep systems intuition, an innovative spirit, and excellent communication skills to collaborate effectively with platform, SRE, and product teams. You are willing to ramp up on the JVM as much of the current stack is Java-based.

Qualifications
BS or MS in Computer Science, Computer Engineering, or equivalent work experience.