Senior Software Engineer, System Orchestration

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, and AstraZeneca 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.

Oxford, UK

Hybrid

We are looking for a highly technical Senior Software Engineer to join our System Orchestration team in System Software at Oxford Ionics. In this role, you will be responsible for building and operating the software that keeps our systems calibrated, decides what they do next and keeps the record of what they did, contributing to the team's mission of keeping our quantum computers running useful work around the clock.

The trapped-ion quantum computers we are building will control 10,000 ions within two years, and all of that has to be kept in tune - settings that drift over minutes, hours and days. Without it a computer does not stop; it quietly starts producing invalid output.

Calibration routines, scientists' experiments and customer workloads all compete for physical hardware, and our team builds the control plane that arbitrates that: it schedules and prioritises programs, hands exclusive access to one at a time and takes it back cooperatively, streams results while a program is still running, and keeps the record of everything that ran. It runs on every quantum computer in our fleet.

Its job is to keep that machine busy and productive: running quantum programs rather than waiting in between, and running them in spec - on a machine still hitting the fidelity it is meant to hit.

The ambition is for that to run without a person in the loop: machines that assess their own readiness, call for the calibrations they need, and keep a full history of how they were tuned.

You’d work closely with the runtime team who own real-time control, the systems teams who build and maintain our quantum computers, and the operators and scientists who run them.

This is a hands-on engineering role and stays that way as you grow in it. You'll play an important part in shaping the services that support our work in building the world's most advanced quantum systems. Previous exposure to quantum systems is not required.

In this position, you will work on a service or subsystem of the control plane end to end, supporting the effective delivery of software every machine in the fleet depends on.

You’ll have the opportunity to set how it behaves under failure and to move live systems onto it safely, contributing directly to the success of the System Software function.

Key responsibilities include:

• Own a service or subsystem end to end - API design, implementation, rollout and ongoing operational health.
• Build closed-loop behaviour that acts on measured system state without a person in the loop.
• Design state machines and their persistence together, so…