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For Companies At a Glance
- Tasks: Design and develop operational tooling for cutting-edge AI systems.
- Company: Join Callosum, a pioneering Intelligent Systems company revolutionising AI.
- Benefits: Competitive salary, equity, healthcare, and relocation support.
- Other info: Collaborative environment with growth potential in technical leadership.
- Why this job: Tackle complex challenges and shape the future of AI technology.
- Qualifications: Master's degree or equivalent experience in a technical field; strong Python skills.
The predicted salary is between 101000 - 192000 £ per year.
About Us
Artificial intelligence scaled on a bet - that bigger models, more identical chips, and more data would keep delivering. As problems become more complex and the requirements of intelligence more diverse, that bet is breaking down. We believe that the next era of AI belongs to heterogeneous intelligence: diverse models on diverse chips, each with distinct strengths, working together into something greater than the sum of their parts. Novel accelerators are emerging from every direction, but no infrastructure exists to bring them together. We are building it.
Callosum is the Intelligent Systems company. We believe intelligence comes from the system, not the model - where chips and models co-evolve to unlock discoveries unreachable under the current paradigm. We are scientists and engineers solving what others consider impossible. If you thrive on hard problems, are passionate and energised by the scale of the challenge, we’d love to hear from you.
About the Role
As the Systems Tooling Engineer, you will be responsible for building the operational layer that connects experimentation to deployment across Callosum's heterogeneous compute stack. You will prototype and validate ideas, and evolve that work into performant, low-level systems in Rust/C++ as it matures. The tooling you build will span every layer of the stack, letting us exploit new compute environments at speed. You will operate across the full development lifecycle - from experiment harnesses and profiling utilities, to production-grade scheduling and observability infrastructure. The role has growth potential toward technical leadership in platform engineering, performance architecture and systems toolchain design, and involves close collaboration with systems and infrastructure engineering teams.
Your Responsibilities
- Fully own the design and development of operational tooling across the heterogeneous compute stack, from early prototype to production-grade system
- Rapidly prototype and validate ideas in Python, then evolve performance-critical components into Rust or C++
- Instrument, profile, and benchmark tooling to identify and eliminate performance bottlenecks across the stack
- Establish and maintain CI/CD pipelines, performance regression tracking, and observability infrastructure
Skills & Qualifications
- Master's or equivalent practical experience in a relevant technical field.
- Strong proficiency in Python for experimentation and rapid prototyping
- Strong foundation in performance-aware systems design, including scalable algorithms, memory layout, concurrency, and asynchronous patterns
- Familiarity with CI/CD and automated testing practices; familiarity with performance regression tracking, and observability/profiling-driven validation
Nice to have
- Experience with Rust/C++ in a production setting
- Exposure to heterogeneous compute environments or HPC workloads
- Familiarity with distributed systems concepts - scheduling, data-plane tooling, or resource allocation
What We Offer
- Competitive Salary: £101,000 - £192,000, determined by skills and experience.
- Equity & Ownership
- Medical and dental 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.
Systems Tooling Engineer in London employer: Callosum Technologies Ltd
Contact Detail:
Callosum Technologies Ltd Recruiting Team
StudySmarter Expert Advice 🤫
We think this is how you could land Systems Tooling Engineer in London
✨Tip Number 1
Network like a pro! Reach out to folks in the industry, attend meetups, and connect with people on LinkedIn. You never know who might have the inside scoop on job openings or can refer you directly.
✨Tip Number 2
Show off your skills! Create a portfolio or GitHub repository showcasing your projects, especially those related to systems tooling or performance engineering. This gives potential employers a taste of what you can do.
✨Tip Number 3
Prepare for interviews by brushing up on relevant technical concepts and practising coding challenges. We recommend using platforms that focus on systems design and performance optimisation to get you ready.
✨Tip Number 4
Apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, it shows you’re genuinely interested in joining our team at Callosum.
We think you need these skills to ace Systems Tooling Engineer in London
Some tips for your application 🫡
Show Your Passion: When writing your application, let your enthusiasm for the role and our mission shine through. We want to see that you're not just looking for a job, but that you're genuinely excited about tackling complex problems in AI and systems engineering.
Tailor Your CV: Make sure your CV is tailored to highlight the skills and experiences that align with the Systems Tooling Engineer role. Focus on your proficiency in Python, Rust/C++, and any relevant projects that showcase your ability to build operational tooling.
Be Clear and Concise: Keep your application clear and to the point. Use straightforward language to describe your experiences and achievements. We appreciate clarity, so avoid jargon unless it’s necessary to explain your expertise.
Apply Through Our Website: We encourage you to apply directly through our website. This ensures your application gets to us quickly and efficiently. Plus, it’s the best way to stay updated on your application status!
How to prepare for a job interview at Callosum Technologies Ltd
✨Know Your Tech Stack
Make sure you’re familiar with the technologies mentioned in the job description, especially Python, Rust, and C++. Brush up on your knowledge of performance-aware systems design and CI/CD practices. Being able to discuss these topics confidently will show that you’re ready to hit the ground running.
✨Showcase Your Problem-Solving Skills
Prepare to discuss specific challenges you've faced in previous roles, particularly those related to tooling and systems design. Use the STAR method (Situation, Task, Action, Result) to structure your answers. This will help demonstrate your ability to tackle complex problems, which is key for a Systems Tooling Engineer.
✨Ask Insightful Questions
Interviews are a two-way street! Prepare thoughtful questions about the company’s approach to heterogeneous compute environments and how they envision the role evolving. This not only shows your interest but also helps you gauge if the company aligns with your career goals.
✨Demonstrate Collaboration Skills
Since the role involves close collaboration with various teams, be ready to share examples of how you’ve successfully worked in a team setting. Highlight any experiences where you contributed to cross-functional projects or helped bridge gaps between different technical disciplines.