Senior Software Engineer, Transport

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, England, UK

Working pattern: Hybrid, two days per week on site (minimum)

The Role:

We are looking for a Senior Software Engineer to join our Transport Software team at IonQ, based in our Oxford office. In this role you will work with physicists to develop ion trap control software, guiding the trajectories of hundreds to thousands of ions in parallel using electromagnetic fields. This will directly contribute to the team's mission of scaling the computational capacity of our trapped-ion quantum computers.

This role will play a central role in shaping the control software that supports our work in building the world's most advanced quantum systems.

Responsibilities:

In this position, you will develop our framework for describing ion transport constraints and, in combination with an electromagnetic model of the ion trap, synthesise voltage waveform data to drive hundreds to thousands of independent DAC channels, with runtime parametrisation to enable closed-loop calibration and mid-circuit feedforward.

You will have the opportunity to accelerate the design and analysis of transport waveforms for trapped-ion quantum computers, and to develop the high-performance data pipelines required to control ion traps of this size and complexity, contributing directly to our roadmap for utility-scale quantum computing.

Key responsibilities include:

• Building the framework that transforms high-level ion transport specifications into voltage waveform data and readies it for runtime execution.
• Supporting the transport waveform team in developing new solvers and physics simulations as components in this framework.
• Collaborating with experimental and theoretical scientists to understand their requirements for experiment and simulation.
• Contributing to the design of transport operations used for quantum circuits, and how they are parametrised and calibrated.
• Interfacing with runtime, non-real-time control, FPGA and electronics teams to shape the overall system architecture.

Requirements:

To be successful you will need strong programming skills in a systems programming language, experience with performance-sensitive computing, and a desire to produce high-quality code appropriate to control software deployed in production. We are looking for someone who can build and iterate on high-performance code in a collaborative, cross-disciplinary environment and contribute effectively within a fast moving, highly technical team.

You'd be a great fit with:

• Familiarity with mathematics and experience with numerical programming, such as in Python.
• • Experience with a systems programming language like Rust or C++. We use Rust in our systems, experience of this language is not essential but a desire to learn it is beneficial.
• Excellent communication skills both within the context of software and across disciplines.
• Experience producing and maintaining high-quality code in a production context.
• Being comfortable with rapidly evolving requirements, and eager to learn and develop your skills.

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!