Callosum raises £7.5m to run multi-model AI across mixed-chip data centres
This article covers Callosum, an AI startup that has raised £7.5m in a growth funding round led by Plural, with backing from the UK’s Advanced Research and Invention Agency (ARIA) and participation from angel investors. The funding will be used to expand the team, scale Callosum’s systems software and secure compute resources to develop a multi-model, multi-chip orchestration approach aimed at reducing vendor lock-in and supporting mixed-chip data centres.
Callosum, an AI startup, has raised £7.5m in a growth funding round led by Plural, with support from the UK’s Advanced Research and Invention Agency (ARIA) and participation from angel investors including Charlie Songhurst, Stan Boland and John Lazar. The cash will be used to grow the team, scale Callosum’s systems software and secure compute resources as it pushes a multi-model, multi-chip approach intended to reduce dependence on single providers and support mixed-chip data centres.
Why it matters
Callosum’s pitch touches on a live technical and strategic problem: modern AI deployments are often built around a narrow set of chips and large single models, which can concentrate cost, performance and supply‑chain risk. Software that can orchestrate different models across diverse chip architectures promises two things — potential performance gains by matching tasks to specialised hardware, and reduced vendor lock-in through multi-cloud and mixed-chip deployment.
That idea has implications for the UK’s tech policy goals. ARIA’s involvement signals public appetite for projects oriented towards sovereign AI infrastructure and for R&D that could be deployed across domestic data centres rather than relying on a single global provider.
Inside the product
Callosum builds systems-level orchestration software that coordinates multiple AI models across different chip types. Rather than moving all workloads onto a single hardware platform, the software routes subtasks to the most appropriate processors and manages communication between components. The company says this approach can improve performance for complex real-world workloads — the press release uses “autonomous computer use” as an example — while lowering costs by extracting efficiencies from chip diversity.
The platform is designed for multi-cloud deployment and, according to Callosum, already works with cloud partners including AWS, Google and Microsoft. The firm intends to use the new funding both to expand engineering capacity and to secure the compute resources needed to test and scale mixed-chip deployments.
Who are the investors?
The round was led by Plural, with backing from the UK’s Advanced Research and Invention Agency (ARIA) and a group of angel investors: Charlie Songhurst, Stan Boland and John Lazar.
Plural’s stated reasoning focuses on the founders and the technical vision. Ian Hogarth, Partner at Plural, said:
Danyal and Jascha have been published in several Nature journals and worked with some of the most prestigious AI and compute organisations in the world. Now they’ve built an incredible team to define and commercialise entirely new ground. Their vision for a multi-model, multi-chip future could be transformative and positions them to compete with the world’s biggest chip and model makers. These are serious founders tackling a serious mission, which is exactly what we look for at Plural.
ARIA’s participation aligns with its remit to fund high‑risk research and innovation that could underpin new UK capabilities in critical areas such as data centre architecture and sovereign compute. The presence of experienced angel investors signals additional private support for the founders’ long-term commercialisation path.
If you're researching potential backers in this space:
- Explore our list of AI venture capital firms in the UK
- Browse our directory of AI angel investors in the UK
Founder perspective
Callosum was founded by Danyal Akarca and Jascha Achterberg, who began working together during their PhDs at Cambridge on topics spanning the brain, computing and AI. Their research has been published in several Nature journals, and their CVs include time at Intel and collaboration with Google DeepMind.
Danyal Akarca, Co-founder at Callosum, said:
Big labs are currently betting that one model will rule them all. We think that's wrong and our work proves this. Nature shows that real intelligence emerges from many systems working together. We’ve brought together incredible talent to enable a paradigm shift in how we build intelligent systems to solve real-world problems, with the infrastructure to make that possible, on any chip, anywhere in the world.
Jascha Achterberg, Co-founder at Callosum, said:
Everyone assumed chip diversity was a disadvantage to be managed. We saw the opposite, that it's an advantage to be exploited. We're not optimising one algorithm on top of the existing stack. We're using software to control all the levers across the entire system, extracting benefits from diversity that others dismiss. Plural understands this mission and we're excited to build alongside them.
The bigger picture
Callosum’s funding sits at the intersection of two broader trends: technical interest in heterogeneous compute — combining CPUs, GPUs, TPUs and other accelerators — and policy moves that aim to bolster domestic AI capability. Tech firms and cloud providers continue to develop specialised hardware, and orchestration software that can span those devices could become important infrastructure.
For UK and European observers, the deal is notable for ARIA’s involvement and for the focus on multi-cloud, multi-chip deployment rather than a single-provider model. If Callosum’s approach proves commercially viable at scale, it could influence how enterprises and data centres think about procurement and resilience in AI stacks.
The outcome will be worth watching for anyone tracking the UK AI ecosystem, compute sovereignty debates and the practical limits of “one model, one chip” approaches across Europe and beyond.
They've invested in Callosum
Get to know these AI investors
Click here for a full list of 7,526+ startup investors in the UK