Senior Software Engineer, Back end (Opal Platform)

Matchbox; Sydney; Hybrid; AUD 130,000 - 190,000; Full time

Job summary

Q-CTRL in Sydney is seeking a Senior Back-end Software Engineer for the Opal Platform to own Python APIs and microservices, delivering REST and GraphQL interfaces. You will implement working software from product stories and collaborate with Product, Design and Research teams to ship value.

You will mentor teammates, improve reliability, performance, and security of distributed systems, and help shape AI-assisted development workflows using tools like Copilot.

Qualifications

• 5+ years in professional software development, including 3+ years in Python.
• Experience building web APIs (REST/GraphQL) with Django or FastAPI.
• Familiarity with OIDC/OAuth2 and Keycloak.
• Strong testing habits, BDD and CI/CD.
• Clear communication across teams; mentoring mindset.

Responsibilities

• Design, build, test, and document Python APIs and microservices.
• Improve reliability, performance, and security of distributed systems.
• Review pull requests with care; maintain code quality.
• Collaborate with Product, Design, and Research teams.
• Mentor teammates and share knowledge.

Skills

Python

REST APIs

GraphQL

Django

FastAPI

AI tools in dev

OIDC/OAuth2

Testing (BDD)

CI/CD

Mentoring

Communication

Education

Bachelor's degree in Computer Science

Tools

Ray

RabbitMQ

Keycloak

Job description

# Senior Software Engineer, Back end (Opal Platform)Q-CTRLHybrid • SydneyFull-Time / Permanent## Role OverviewAbout the teamAt 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 the roleAs a Senior Back-end Software Engineer in the Opal Platform team you will be responsible for managing how users and partners can access the Q-CTRL products and how our own services interact with our platform.You'll share ownership of the Python APIs and microservices that power Q-CTRL's quantum software products, used by customers worldwide. You'll work in an AI-native engineering team, where agentic tools handle the routine work so you can focus on design, quality and impact.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 openlyIdeally 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 experienceIt 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)