Software Engineer, Back - end (boulder Opal)

Software Engineer, Back-end (Boulder Opal)

Founded in 2017, Q-CTRL has grown to become the global leader in quantum. We're using control to solve the hardest problems facing quantum technology, improving hardware performance and accelerating pathways to useful quantum computers and other technologies. As a product-led company, we bring together diverse teams such as product, design, engineering and research to help achieve our mission of making quantum technology useful. Join us to help shape the quantum future.

As one of the fastest growing companies in the quantum sector, we've had a number of key milestones:

- In November 2023, we announced an industry-first partnership with IBM Quantum Services, natively integrating our performance management software with all IBM quantum computers. Building off of this relationship, in September 2024 we started offering two services via IBM's new Qiskit Functions Catalog as an inaugural partner.

- Designed and moved our Global HQ offices and lab space into the first purpose-built (and award winning) commercial and research facility for a quantum technology company in Australia.

- Continued to deliver real world outcomes across the quantum sectors, with our work with Australian Defence on software-ruggedized quantum sensing for navigation without GPS, as featured in the New York Times.

- In October 2024, we announced our record breaking expansion of our Series B funding round to USD $113M, with $59M USD of new capital.

- Grew our global presence to include Los Angeles, Berlin, and Oxford - as well as the recently announced office in San Francisco.

From educating the workforce on how quantum computing works, to building the next generation of quantum sensors, to delivering massive performance gains for end-users, it all starts with hiring the right talent. If you want to help us build the Quantum future, read on.

As a Software Engineer on the Boulder Opal team, you will work with brilliant engineers and researchers to design and build a scalable, high-performance backend system while directly contributing to our quantum controller infrastructure.

A key part of your role will be maintaining and evolving the compiler stack that translates OpenQASM3 + OpenPulse programs for low-level quantum controllers, bridging the gap between high-level quantum programming and physical execution on QPUs. You will collaborate with cross-functional teams, product, infrastructure, frontend, and research, ensuring end-to-end delivery of cutting-edge solutions that power our SDKs and cloud-based offerings.

This role is ideal for someone passionate about backend engineering and systems-level programming, with an interest in quantum computing and scientific software.

What you'll be doing:

• Build the backbone of quantum tech: Design, develop, and optimize scalable backend services in Python (with opportunities to work in Rust or C++).
• Own the compiler stack: Maintain and evolve the compiler that translates OpenQASM3 + OpenPulse programs into low-level controller instructions.
• Bridge research and engineering: Work closely with world-class researchers and quantum engineers, translating experimental needs into production-ready code and debugging real-world execution challenges.
• Experiment on quantum hardware: Get hands-on with QPUs, validating compiler output and controller behaviors through real device experiments.
• Engineer for performance: Deliver high-efficiency service-to-service communication using modern protocols (gRPC, GraphQL, REST).
• Raise the bar on quality: Shape and enforce best practices for clean, secure, and reliable code while contributing to robust testing and documentation.
• Shape the future stack: Help define the software practices, tools, and design patterns that will power the next generation of quantum control systems.
• Deliver end-to-end solutions: Collaborate with product, frontend, and infrastructure teams to ship integrated solutions used across Q-CTRL's products.
• Other duties within the Employee's skills and experience, or with reasonable training.

Ideally you'll have:

• Bachelor's degree in Computer Science, Engineering, or related field.
• 3+ years of backend software development experience with Python, Rust, C++, or similar.
• Proven experience writing maintainable, testable Python code in a professional setting.
• Strong collaboration and communication skills across cross-functional teams.
• Strong problem-solving skills with a proactive, solutions-focused mindset.

It would be fantastic (but not essential) if you bring:

• A curiosity for compiler design concepts or experience working with intermediate representations (IRs).
• Familiarity with OpenQASM3, OpenPulse, Qiskit, or other quantum programming frameworks.
• Hands-on experience with modern APIs like gRPC, GraphQL, or REST.
• Comfortable working with cloud platforms (AWS, GCP, Azure) and cloud infrastructure tools.
• Knowledge of distributed systems, microservices, or database scaling techniques.
• Familiarity with popular Python web frameworks (Django, Flask, FastAPI).
• An eye for data visualization with tools like Plotly, Dash, or Jupyter.
• Experience thriving in a start-up or scale-up environment where speed and collaboration matter.
• Experience designing efficient algorithms, statistical models, or data pipelines to process and analyze large-scale experimental datasets.
• Experience with implementing CPython extension modules for accelerating Python programs.

Q-CTRL aims to bring together cross-functional teams from many different backgrounds to help achieve our goals - we strongly encourage you to apply even if you do not meet all of the requirements mentioned in the job posting.