Software Engineer, Non-Realtime Controllers

About IonQ:

IonQ, Inc. [NYSE: IONQ] is the world’s leading quantum platform and merchant supplier - delivering integrated quantum solutions across computing, networking, sensing, and security. IonQ’s newest generation of quantum computers, the IonQ Tempo, is the latest in a line of cutting-edge systems that have been helping customers and partners including Amazon Web Services,andAstraZeneca achieve 20x performance results and accelerate innovation in drug discovery, materials science, financial modeling, logistics, cybersecurity, and defense. In 2025, the company achieved 99.99% two-qubit gate fidelity, setting a world record in quantum computing performance.

Headquartered in College Park, Maryland, IonQ has operations in California, Colorado, Massachusetts, Tennessee, Washington, Italy, South Korea, Sweden, Switzerland, Canada, and the United Kingdom. Our quantum computing services are available through all major cloud providers, while we also meet the needs of networking and sensing customers across land, sea, air, and space. IonQ is making quantum platforms more accessible and impactful than ever before.

Location: Oxford, UK

Office commitment: Hybrid

The Role:

Quantum is now, and it's built here. Oxford Ionics, now part of IonQ, is pioneering the next generation of quantum computing. Using our world-leading trapped-ion technology, we're building the most powerful, accurate and reliable quantum systems to tackle problems that today's supercomputers cannot solve.

We're looking for an enthusiastic and highly technical Software Engineer for our Non-Realtime Controllers team who will thrive in our dynamic cross-disciplinary environment.

In this role, you will be responsible for working closely with our software engineers, our systems team, and our quantum scientists to build and operate the software that controls the hardware surrounding our quantum computers, contributing to the team’s mission of enabling our systems team to operate the physical quantum computers and our science teams to experiment building towards fault tolerant computation. Previous exposure to quantum systems is not required.

You’ll play an important part in shaping the non-realtime controllers, the system operations and services that support our work in building the world’s most advanced quantum systems.

Responsibilities:

In this position, you will work hands-on with hardware control end to end, from the device protocol up to a service running reliably across our fleet, supporting the effective delivery of non-realtime controllers that ensure that the critical supporting hardware of a quantum computer is observable, controllable and reliable (from cryogenic compressors to lasers, wavemeters, and various sensors).

You’ll have the opportunity to own areas of the hardware control surface end to end, from the device protocol up to a service running reliably across our fleet, contributing directly to the success of building utility-scale quantum computers.

Key responsibilities include:

• Own a group of device controllers end to end, covering API design, implementation, rollout and ongoing operational health
• Make services robust against the ways real instruments fail and strengthen observability, health checking and alerting
• Bring devices onto our current framework, and roll the result out across the fleet without disrupting running experiments
• Work closely with the software. systems and science teams who depend on these services, and to ensure our work integrates seamlessly with the wider software architecture

Requirements:

To be successful, you will need strong programming skills in a systems programming language and hands-on experience interfacing with hardware, and a track record of making software behave well against unreliable external dependencies. We’re looking for someone who can quickly iterate on low-level code in a collaborative, cross-disciplinary, environment and contribute effectively within a fast moving, highly technical team.

You’d be a great fit with:

• Strong programming skills in one or more systems programming languages and the appetite to work in a Rust codebase
• Experience with some hardware instrument and communication protocols (e.g. SCPI, serial, TCP/IP, USB, or similar)
• Comfortable owning the production behaviour of what you build, not just its correctness in test
• Excellent communication skills both within software and across disciplines, and an interest in helping other engineers get better at the craft without wanting to stop building yourself

Benefits

Be part of a team that’s shaping the future of quantum. We offer more than just a role, you’ll join a world class community of scientists, engineers and innovators working to unlock the full potential of quantum computing.

We offer a range of benefits, including opportunities to further your career alongside industry leaders, a competitive salary with IonQ stock options, an annual performance bonus, generous annual leave, flexible hybrid working, private medical and dental insurance for you and your family, and much more.

Join us and be part of the future of quantum computing.

We’re proud to be an equal opportunity employer and welcome applicants from all backgrounds.

Compensation will vary based on individual factors such as education, qualifications, and experience of the final candidate(s), specific office location, and calibration against relevant market data and internal team equity. Posted base salary figures are subject to change as new market data becomes available. Our benefits include comprehensive medical, dental, and vision plans, matching 401(k), unlimited PTO and paid holidays, parental/adoption leave, legal insurance, and a home technology stipend. Details of participation in these benefit plans will be provided when a candidate receives an offer of employment.

At IonQ, we believe in fair treatment, access, opportunity, and advancement for all while striving to identify and eliminate barriers. We empower employees to thrive by fostering a culture of autonomy, productivity, and respect. We are dedicated to creating an environment where individuals can feel welcomed, respected, supported, and valued.

We are committed to equity and justice. We welcome different voices and viewpoints and do not discriminate on the basis of race, religion, ancestry, physical and/or mental disability, medical condition, genetic information, marital status, sex, gender, gender identity, gender expression, transgender status, age, sexual orientation, military or veteran status, or any other basis protected by law. We are proud to be an Equal Employment Opportunity employer.

US Technical Jobs. The position you are applying for will require access to technology that is subject to U.S. export control and government contract restrictions. Employment with IonQ is contingent on either verifying “U.S. Person” (e.g., U.S. citizen, U.S. national, U.S. permanent resident, or lawfully admitted into the U.S. as a refugee or granted asylum) status for export controls and government contracts work, obtaining any necessary license, and/or confirming the availability of a license exception under U.S. export controls. Please note that in the absence of confirming you are a U.S. Person for export control and government contracts work purposes, IonQ may choose not to apply for a license or decline to use a license exception (if available) for you to access export-controlled technology that may require authorization, and similarly, you may not qualify for government contracts work that requires U.S. Persons, and IonQ may decline to proceed with your application on those bases alone. Accordingly, we will have some additional questions regarding your immigration status that will be used for export control and compliance purposes, and the answers will be reviewed by compliance personnel to ensure compliance with federal law.

US Non-Technical Jobs. Due to applicable export control laws and regulations, candidates must be a U.S. citizen or national, U.S. permanent resident (i.e., current Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum. Accordingly, we will have some additional questions regarding your immigration status that will be used for export control and compliance purposes, and the answers will be reviewed by compliance personnel to ensure compliance with federal law.

If you are interested in being a part of our team and mission, we encourage you to apply!