Senior Software Engineer, System Orchestration

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, 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.

Location: Oxford, UK
Office commitment: Hybrid

The Role:

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.

Responsibilities :

This is a hands-on engineering role, balancing delivery of your own areas with support for the teams and scientists who depend on them.

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.

• Bring devices onto our current framework, and roll the result out across the fleet without disrupting running experiments.

• Improve the shared framework where a problem turns out to be common to many controllers rather than specific to one.

• Work closely with the systems teams and scientists who depend on these services, and strengthen observability, health checking and alerting.

• Raise the standard of the code around you through review, and bring less experienced engineers on by working alongside them.

Requirements:

To be successful, you will need experience building stateful services that stay correct under failure, and a track record of changing a load-bearing system while people depend on it. We're looking for someone who can own a problem area with little supervision and contribute effectively within a fast moving, highly technical team.

You'd be a great fit with:

• Strong systems engineering skills. Our System Orchestration layer is written in Rust, so either solid Rust experience or deep proficiency in another systems language and the appetite to work in a Rust codebase, including async programming.

• Experience designing and operating networked services (such as gRPC or REST), with a real grasp of error handling, observability and failure modes.

• Real experience with a relational database as a source of truth - schema design, migrations against live data, and transactions. We use PostgreSQL.

• A track record of getting lifecycle and concurrency right: state machines, timeouts, leases, retries, and the failure modes that only show up under load.

• Experience with a scheduler, workflow engine or job queue - Temporal, Airflow, Celery, Slurm, or one you built - or with event-driven systems that react to changes in state.

• A habit of settling design questions in writing, with options weighed as peers.

• Comfort owning the production behaviour of what you build, not just its correctness in test.

• Excellent communication skills both within software and across disciplines.

• An interest in helping other engineers get better at the craft, without wanting to stop building yourself.

Additional useful experience would include running containerised services in production, Kubernetes, distributed tracing, closed-loop systems that act on measured state, and scientific computing or research facilities.…

Source: Arbeitnow (https://www.arbeitnow.co.uk/jobs/companies/ionq/senior-software-engineer-system-orchestration-oxford-48121)