Lead Heterogeneous Interconnects & RDMA Networking

Callosum; Greater London; On-site; GBP 90,000 - 130,000; Full time

Benefits offered by this job

Competitive salary

Equity & Ownership

Private healthcare

Visa sponsorship and relocation to the

London office support

Inclusive workplace

Job summary

Callosum is hiring to build the communications backbone for heterogeneous AI accelerators in a London-based role. You will own the design of interconnects, RDMA paths and memory movement to enable efficient collaboration across accelerator types, processing protocols, and software layers.

The role focuses on reducing latency, optimizing cross-device memory transfers, and shaping the technical strategy for scalable, unified systems across the stack.

Qualifications

• Deep understanding of networking and communication systems.
• Experience with high-performance data movement such as RDMA or similar.
• Ability to trace bottlenecks across abstraction layers and optimise interconnects.
• Willingness to question abstractions and simplify systems for workload requirements.

Responsibilities

• Characterise and optimise communication paths between accelerators.
• Develop high-speed data movement across heterogeneous hardware.
• Design flexible state transfer mechanisms across device types.
• Evaluate scale-up and scale-out interconnect fabrics for future architectures.

Skills

Networking systems

RDMA

Programmable NICs

DPUs

Job description

Callosum is hiring to build the communications backbone for heterogeneous AI accelerators in a London-based role. You will own the design of interconnects, RDMA paths and memory movement to enable efficient collaboration across accelerator types, processing protocols, and software layers.

The role focuses on reducing latency, optimizing cross-device memory transfers, and shaping the technical strategy for scalable, unified systems across the stack.