
Mechanical Engineer
Lumai
Posted 5 days ago
The Opportunity
Lumai is redefining how the world computes. We are an ambitious, venture-backed UK startup pioneering a breakthrough AI accelerator for data centers which uses 3D optical compute. Our radical technology uses light to perform computation at orders of magnitude faster speeds and at far greater scales than ever before, all whilst consuming far less energy than traditional approaches.
Lumai is unlocking performance and efficiency gains that could transform the economics of AI and compute infrastructure and reshape how intelligence scales globally.
If you are passionate about bringing groundbreaking technology to market, and want to be part of a team pushing the boundaries of what is physically possible, Lumai is where you can make it happen.
About Lumai
Founded in 2022, Lumai is a University of Oxford spinout using optical processing to accelerate large language models (LLMs) and other transformer-based AI systems. The team combines expertise in optical computing, machine learning, and physics.
Lumai has already secured over $15 million in investment from leading deep-tech investors like Constructor Capital, IP Group, PhotonVentures and government grants, and is scaling rapidly to deploy the fastest optical compute currently available globally.
The Role
We are seeking a skilled Mechanical / Optomechanical Engineer to join our Oxford-based team. The ideal candidate will be responsible for designing, analysing, and improving mechanical systems and components for our product. The role involves collaborating with cross-functional teams to develop innovative solutions that meet project objectives and industry standards. We welcome applicants both from earlier career and more experienced engineers.
What You'll Do
Design and Development
Conceptualise, design, and develop compact, robust optomechanical systems for products, prototypes and optical testing. Develop optical mounting and alignment techniques working with the optical team
Work with the optical and electronics teams to produce system prototypes
Utilise CAD software to create detailed designs and engineering drawings
Conduct structural, material, and thermal analysis to optimise the performance and reliability of optomechanical systems
Participate in prototype builds, testing, and validation of optomechanical systems to ensure compliance with design specifications and performance requirements
Project Management
Manage multiple projects simultaneously, ensuring adherence to deadlines and budget allocation
Coordinate with internal teams and external stakeholders to define project requirements and deliverables
Monitor project progress, identify potential risks, and implement mitigation strategies as needed
Documentation and Reporting
Prepare detailed documentation, including design specifications, technical reports, and project documentation
Communicate project status updates, technical findings, and recommendations to key stakeholders
Maintain accurate records of design iterations, test results, and project-related documentation
What We're Looking For
Must-Have
Effective communication and interpersonal skills
Undergraduate or master’s degree in mechanical engineering or related field
Minimum of 2 years of experience in mechanical design and analysis
Strong understanding of mechanical principles, and materials science
Proficiency in CAD software (e.g., SolidWorks, AutoCAD) and simulation tools (e.g., ANSYS)
Ability to work independently and collaboratively in a fast-paced environment
Strong Preference For
Experience with optical products (e.g. projector, microscopes, Lidar, laser systems etc)
Knowledge and practical experience of optomechanical system design
Familiarity with the basic principles of optical design is desirable, but not essential
Proficiency in structural simulation tools (e.g. ANSYS)
Experience in taking technology from concept, to prototype, to product
Compensation & Benefits
Highly Competitive Salary: We are not saying our salary is a blank check, but let's just say it won't be a source of your stress
Share Option Scheme: We are all in this together! We believe in shared success while we build the Lumai of tomorrow
Pension Scheme: Plan for retirement with AVIVA
Private Health Insurance: We firmly believe that you come first, and a happy you is a healthy you! Look after yourself and your loved ones with AXA
Cycle to Work: Spread the cost of a bike, a bike and accessories or just accessories and save on tax
L&D Allowance: Stay at the forefront of your field with a £500 annual development budget
Subsidised On-site Lunches: Enjoy on-site healthy meals at half the price, as Lumai covers 50% of the cost
Holidays: Enjoy some deserved "me time" with 25 days paid holiday (plus bank holidays) per year
Socials: Be part of an inclusive community enjoying occasional all-company off-sites, lunches and socials
Interview Process
Our process is four stages. An initial conversation with our HR team to understand what you want from the role and what we want from it. Two technical sessions with various members of our engineering team. Finally, an HR-team session covering scope, terms, and any final questions. We aim to move fast on candidates we are excited about; expect roughly three to four weeks end to end.
Lumai is an equal opportunity employer. We make hiring decisions on merit, scope-fit, and the strength of the working relationship we expect to build with each hire. Applications welcome from candidates of any background. If you are not sure whether you are a fit, send a note anyway.

