Senior Software Engineer: Architecture and Engineering Practices

• A unique opportunity to work on real superconducting quantum hardware
• Career path
• Strong mentorship and technical growth
• Competitive salary

🏥 Private health insurance

💳 Cobee flexible compensation (transportation, meals, and childcare support)

⏰ Flexible working hours

🏡 Hybrid work model

Qilimanjaro Quantum Tech is a Barcelona-based quantum computing company building full-stack analog quantum computers on superconducting fluxonium qubits. Founded in 2019 as a spin-off from the Barcelona Supercomputing Center (BSC), the University of Barcelona (UB) and the Institute of High-Energy Physics (IFAE), the company exists to make quantum computing useful in the near term, rather than in a distant error-corrected future.

Qilimanjaro designs, builds and operates the complete stack: the quantum hardware, the control layer, and the software that orchestrates it.

We are looking for a Senior Software Engineer to design and build software for quantum computing and improve our engineering practices. You will join the Software team in the department developing software to control quantum hardware, and work across that department and the one developing software development kits and programming tools. You will report to the department’s Team Lead, who is responsible for people management, and collaborate with its Tech Lead and the division’s Staff Engineer on technical direction.

This is a hands-on individual contributor role: you will turn architecture decisions into tested, maintainable code, improve development workflows and mentor through implementation and review. You should be interested in quantum computing and willing to learn the domain needed for your work; a physics background is not required.

Main ownership areas: Responsibilities

• Design and implement maintainable components, interfaces and migrations, documenting trade-offs and validating changes with the relevant technical owners.
• Work with engineers developing hardware-control software and software development kits on shared architecture, libraries, integration and developer tooling.
• Turn agreed engineering practices into working examples and automated checks for tests, documentation, dependencies and code review.
• Improve the workflow from a written need through implementation, verification and a supportable handover.
• Use AI tools for implementation and review where useful, and verify their output with tests, engineering judgment and the company’s approved tool and data policies.
• Partner with infrastructure and operations engineers on the services these workflows need; own the software code, test evidence and integration requirements.
• Mentor through pairing, design discussions and review, enabling other engineers to maintain the improvements.
• Track review waiting time, rework and defects alongside delivery lead time, and use that evidence to choose the next improvement.