---
title: 'Expression of Interest - Intelligent Systems Engineer at Callosum'
canonical: 'https://feeny.ai/job/expression-of-interest-intelligent-systems-engineer-callosum-london-zkv70tt02hyd'
type: 'job'
last_seen: '2026-09-10'
---

# Expression of Interest - Intelligent Systems Engineer at Callosum 

- **Company:** Callosum 
- **Location:** London, United Kingdom
- **Employment:** full-time
- **Work type:** onsite
- **Posted:** 2026-02-25
- **Last confirmed live:** 2026-09-10
- **Apply:** https://jobs.ashbyhq.com/callosum/49df3034-21c5-47da-b63f-22bf1ab7b893

## Job description

## 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.

Open Application We're always looking for exceptional engineers who want to work on the hardest problems in AI infrastructure - bringing novel accelerators to life, building the systems that orchestrate them, and charting the new territories of what heterogeneous compute can do. If you think you have unique skills to contribute, or have experience in any of the following, we'd love to hear from you:

- High-performance systems and low-level performance engineering
- Inference infrastructure, orchestration, or distributed systems
- Hardware bring-up, kernel development, or accelerator programming
- Simulation, modelling, or workload design

This is a general interest form rather than an application for a specific role. We prioritise active applicants for open positions, but we review all submissions on an ongoing basis and will reach out when we see a strong match. If you spot a specific role that excites you, we'd encourage you to apply directly.

## About Callosum 

## Company Overview
- **One-liner**: Callosum is building the infrastructure where heterogeneous chips and intelligence co-evolve to solve the world’s hardest problems, challenging the AI industry’s monoculture of identical hardware.
- **Entity Type**: Private (Seed stage; $10.25M funding)
- **Headquarters**: London, United Kingdom
- **Founded**: 2025
- **Founders**: Danyal Akarca and Jascha Achterberg

## Core Business
- **Primary industry**: AI infrastructure / research services
- **Target customers**: AI teams tackling the hardest problems (enterprise, research labs, government), and chip makers whose silicon will change the world (B2B, enterprise)
- **Mission or purpose**: To unlock a new frontier of heterogeneous scale, where a plurality of chips and compute primitives give rise to systems of intelligence we haven’t yet imagined.

## Products & Services
- **Heterogeneous Compute Orchestration Platform**: A software platform that enables different AI models to work together across chips from various manufacturers (e.g., photonic, thermodynamic, analog, wafer-scale). It orchestrates components into a system that interacts, communicates, and collaborates, reducing dependence on any single provider and unlocking orders-of-magnitude improvements in capabilities and cost.

## Market Standing
- **Valuation/Market Cap**: Not disclosed
- **Key Metric**: Total funding – $10.25M (Seed round led by Plural, with participation from ARIA and angel investors, announced February 2026)
- **Notable Investors/Partners**: Plural (lead investor), ARIA (Advanced Research and Invention Agency, UK government body), UK Sovereign AI Fund (first company backed by the fund), plus 22 other world-class investors
- **Growth Signals**: 
  - First company backed by the UK Sovereign AI Fund (announced April 2026)
  - ARIA’s Scaling Inference Lab (£50m commitment) – Callosum is using the lab to prove its AI chips can compete against Nvidia
  - Headcount of 14 employees with 6.2% monthly growth, expanding London team
  - Research published in Nature journals and collaborations with Google DeepMind
  - Strong engagement on LinkedIn (3,667 followers) and positive reactions to funding announcements

## Competitive Advantages
- **Heterogeneous-first approach**: Unlike the industry trend of scaling identical chips, Callosum treats chip diversity as an advantage to be exploited, not a disadvantage to be managed.
- **Full-stack capability**: Operates across the entire stack – from silicon to algorithms to systems – rethinking each in context of the others.
- **Brain-inspired foundation**: Founders’ background in neuroscience (Cambridge PhDs) informs a design philosophy where intelligence emerges from many systems working together, similar to the human brain.
- **Sovereign AI positioning**: Backed by UK government bodies (ARIA, Sovereign AI Fund), offering a counterpoint to Silicon Valley concentration of power.

## Strategic Focus
- **Current priorities**: Expand the London-based team, scale the orchestration software, and prove heterogeneous compute in ARIA’s Scaling Inference Lab.
- **Direction for growth**: Enable a new paradigm of heterogeneous intelligence, where any chip can be used anywhere in the world, reducing reliance on Nvidia and opening new frontiers of discovery.

## Why Work Here
- **Culture highlights**: Mission-driven, high-agency environment; described as “exceptional, high-agency people who want to do the best work of their lives.” The team includes world-class scientists, engineers, and visionaries from disciplines like neuroscience, AI, and chip design.
- **Remote/hybrid/office policy**: Likely office-based in London (all 14 employees are in the UK; job postings mention London office).
- **Notable perks or engineering culture**: 
  - Interdisciplinary collaboration (neuroscience, AI, hardware, software)
  - Opportunity to work on frontier research and production systems simultaneously
  - Strong backing from top-tier investors and UK government
  - Tech stack includes Kubernetes, gRPC – modern infrastructure
  - High bar for talent, with alumni going to top VC firms and tech companies

## Sources
1. [callosum.com](https://www.callosum.com/)
2. [callosum.com/team](https://www.callosum.com/team)
3. [uk.linkedin.com](https://uk.linkedin.com/company/callosumtechnologies)
4. [tech.eu](https://tech.eu/2026/02/26/callosum-challenging-ai-silicon-valley-monoculture-comes-out-of-stealth/)
5. [jobs.ashbyhq.com](https://jobs.ashbyhq.com/callosum/6fa6e6cd-f7be-4853-9cb5-18856d510565)

## Other roles at Callosum 

- [Head of Physical Infrastructure](https://feeny.ai/job/head-of-physical-infrastructure-callosum-london-jhpp77xzs3af) — London, United Kingdom
- [Security Lead - Member of Technical Staff](https://feeny.ai/job/security-lead-member-of-technical-staff-callosum-london-cyn9vm0a4a15) — London, United Kingdom
- [ML Research Scientist - Member of Technical Staff](https://feeny.ai/job/ml-research-scientist-member-of-technical-staff-callosum-london-npmwbydhvk47) — London, United Kingdom
- [Research Engineer, Evals - Member of Technical Staff](https://feeny.ai/job/research-engineer-evals-member-of-technical-staff-callosum-london-njdzsj6d6ht0) — London, United Kingdom
- [Agent Runtime & Systems - Member of Technical Staff](https://feeny.ai/job/agent-runtime-systems-member-of-technical-staff-callosum-london-xrk56738n51m) — London, United Kingdom
- [ML Research Engineer - Member of Technical Staff](https://feeny.ai/job/ml-research-engineer-member-of-technical-staff-callosum-london-z4wg41dc04vz) — London, United Kingdom
- [Evolutionary Optimisation - Member of Technical Staff](https://feeny.ai/job/evolutionary-optimisation-member-of-technical-staff-callosum-london-n845f38evfv8) — London, United Kingdom
- [Research Engineer, Benchmarking - Member of Technical Staff](https://feeny.ai/job/research-engineer-benchmarking-member-of-technical-staff-callosum-london-yhx056n5cgaa) — London, United Kingdom
- [Networking & Interconnect Systems - Member of Technical Staff](https://feeny.ai/job/networking-interconnect-systems-member-of-technical-staff-callosum-london-5wm175a1vydv) — London, United Kingdom
- [Site Reliability - Member of Technical Staff](https://feeny.ai/job/site-reliability-member-of-technical-staff-callosum-london-pnq27m8qkyfe) — London, United Kingdom