Heterogeneous Compute Orchestration - Member of Technical Staff

About Us

We’re living through a Cambrian explosion of intelligence: new models and new chips, each specialised for different tasks, are arriving all at once. The result is a new era for AI, one of radical heterogeneity.

Callosum is the Intelligent Systems Company. We believe the next generation of AI won't be defined by any single model or chip, but by intelligent systems in which hardware and intelligence co-evolve. We are building the infrastructure that unifies heterogeneous compute across the full stack. This opens a new axis of scaling intelligence: a dynamic system that tailors itself to what each workload actually needs, whether that's speed, cost, precision, or whatever unit comes next.

The last era scaled on a different bet: one bigger model, more of the same chip, more data. That bet is running into structural limits. Frontier models offer extraordinary capability at unsustainable cost, one that today's monolithic infrastructure was never designed to serve.

Our founding principle is that intelligence comes from many specialised systems working together, not from any single component. We build the software orchestration layer that co-evolves models, workflows and silicon into one system, delivering inference tailored to every workload, and demonstrating orders-of-magnitude leaps in capability and cost.

Because our software spans the full stack, our engineering team works directly with heterogeneous accelerators and frontier silicon, including Cerebras, d-Matrix, Intel, NVIDIA, AMD, Normal Computing, Tenstorrent, GreatSky, and Mixx. We are not stopping at today's chips: each new generation of silicon unlocks algorithms that couldn't run before, and we intend to be first to them, every time. If we get it right, it will belong to everyone building on it - not to any single vendor.

In our latest funding round, we raised $100M, led by Atomico with participation from Plural, DCVC and the UK Sovereign AI Fund’s first investment. With this, we are building the infrastructure for the next era of intelligence.

We are engineers and scientists based in London, working across the full depth of the stack. We are curious, intellectually honest, and building what doesn't exist yet. If you thrive on uncharted territory and are energised by the scale of the challenge, we'd love to hear from you.

About the Role

Callosum believes that orders of magnitude improvements in AI systems will come through application-aware orchestration across heterogeneous hardware. Today, computational workloads are largely mapped onto predefined execution environments, with limited ability to exploit the diversity of emerging accelerators. We are building infrastructure that treats compute as a unified, dynamic system, where workloads can be understood and executed according to the capabilities of the hardware available.

This role sits at the centre of Callosum's orchestration stack, determining how computation is distributed and coordinated across heterogeneous resources. You will extend the algorithms and systems that translate computational workloads into efficient execution strategies, working across scheduling, resource allocation, performance modelling, and representations of computation. Drawing on ideas from distributed systems, optimisation, and compilers, you will help define how heterogeneous compute operates as one system rather than a collection of independent machines.

What You'll Build

• Develop orchestration systems that coordinate computational workloads across heterogeneous accelerators and distributed infrastructure.

• Design scheduling and resource allocation algorithms that optimise performance, cost, and utilisation across diverse hardware.

• Extend mechanisms for representing and transforming workloads into efficient distributed execution strategies.

• Develop workload-aware optimisation techniques that respond to changing demand and system conditions.

• Work across inference engines, networking, and accelerator systems to translate orchestration decisions into efficient execution.

What Sets You Apart

• Strong experience building distributed systems, scheduling infrastructure, or computational execution frameworks.

• Deep understanding of resource allocation, scheduling algorithms, and performance trade-offs in large-scale systems.

• Familiarity with compiler concepts, computational graphs, query planning, or other approaches to representing and transforming computation.

• Experience reasoning about dynamic workloads, system performance, and optimisation under resource constraints.

• Strong systems engineering instincts, with an ability to design abstractions that generalise across unfamiliar hardware and workloads.

What We Offer

• Competitive Salary, determined by skills and experience

• Equity & Ownership

• Private healthcare

• We offer Visa sponsorship and relocation benefits to hire the best in the world

• We work in person at our London office. You'll have the tools, space and setup to do your best work, and if you have specific needs, just tell us

We're committed to building an inclusive workplace where everyone feels welcome, and believe in equal opportunities for all.