Senior Software Engineer, Back end (Opal Platform)

About the team At Q-CTRL, Quantum Computing Engineering is a global team of software engineers and infrastructure experts, combining deep technical expertise with a startup mindset to deliver real impact through software innovation. Our work is underpinned by robust standards, and by embracing the three virtues. Our team excels in areas across back-end, front-end, machine learning, and platform engineering.   We transform Q-CTRL’s world-leading technological breakthroughs into commercial software products with applications across defense, research, and industry. We work closely with Product, Design, and Research teams to accelerate the path to quantum advantage worldwide. About Q-CTRL Q-CTRL is the global leader in AI-powered quantum control infrastructure software. We build the tools that make quantum technology useful, solving the hardest challenges in quantum computing and quantum sensing to deliver real-world impact.   Founded in 2017, we operate globally with offices in Sydney, Los Angeles, San Francisco, Huntsville, Berlin, and Oxford. Our teams bring together technical and multi-disciplinary expertise across the product lifecycle, and we’re hiring talent to help scale every part of the business. We work quickly to turn cutting-edge science into deployable technology.   In 2024 we raised US$113 million in Series B funding, the largest aggregate investment for a quantum software company. Six months later we delivered the first commercial quantum advantage with Ironstone Opal, our field-validated quantum navigation solution for defense and industry.   At Q-CTRL, we prioritize outcomes over hours. We offer flexibility, equity potential, and competitive benefits that reflect our high-performance culture. If you’re ready to help shape the future of quantum, we’d love to hear from you!   Please be advised that our communications will only come from the @q-ctrl.com domain. All our active job postings are available on our company website.   To recruitment agencies, we do not accept unsolicited branded profiles and are not responsible for any fees related to unsolicited resumes.

What you'll be doing:

Designing, building, testing and documenting Python APIs (REST and GraphQL) and the microservices and client packages behind our product features

Turning product intent into working software, using stories (AS A, WHEN, THEN) from the Product team as shared, testable specs

Using AI coding assistants and agentic workflows daily (e.g. Copilot, Claude Code) for implementation, test generation, refactoring and documentation, while owning the quality of what ships

Helping shape how the team uses AI: evaluating tools, writing prompts and guardrails, and sharing what works

Reviewing pull requests with rigour and kindness, including AI-generated code

Improving reliability, performance and security of our distributed systems

Mentoring teammates and sharing knowledge openly

Ideally you'll have:

5+ years of professional software development, including 3+ years in Python

Strong experience building web APIs (REST, GraphQL) with Django or FastAPI

Fluent with AI tools in your development workflow, with good judgement about when to trust, verify or override them

Experience with OIDC/OAuth2 (we use Keycloak)

Sound testing habits (BDD, automated tests, CI/CD)

Clear communication and the ability to communicate with different internal audiences

Comfort moving fast with thought and empathy in a scaleup environment

A degree in computer science or equivalent practical experience

It would be fantastic if you have these skills/experience but not essential:

Experience building with LLMs, agents or MCP

Microservices and distributed systems (we use Ray and RabbitMQ)

Curiosity about quantum computing (no physics background required)