Quantum Applications Software Developer

PsiQuantum's applications team is uniquely focused on algorithms in the fault tolerant regime and is very tightly integrated with quantum architecture development. Within that team, the role of a quantum applications software engineer is to design, build and deploy tools which drive the development of quantum applications for solving the world's most pressing problems. As a crucial member within the team, a quantum application software engineer's job is to work closely with quantum applications architects and engineers to develop software toolkits and workflows, without which the team could not do their job. Such tools include (but are not limited to): quantum simulators, quantum resource estimators, quantum circuit compilation, and domain-specific quantum application integration. This work takes quantum algorithms from concept to reality, may involve close collaboration with external partners on specific use cases, and directly enables the discovery of both new quantum application use-cases and novel algorithmic techniques., Lead the design, development, and deployment of quantum applications software tools to support both internal and external users.Maintain, service and upgrade a high-quality codebase supported by a fast and reliable simulation infrastructure.Work closely with internal and external partners and other members of the quantum applications team to design, implement and analyze quantum algorithms for real-world use cases.Assist with full system analysis to evaluate and optimize resource requirements for fault tolerant computations.Assist with the optimization of quantum algorithms at the subroutine, circuit, and compiled gate-set level.

Graduate degree in Physics, Math, or Computer Science or equivalent required (MSc or PhD). Practical experience in quantum computing, programming quantum applications, or quantum circuit compilation.5+ years professional experience programming and releasing production code in Python, C++, or similar languages.Experience with quantum algorithms or compiling in the regime of fault tolerant gates preferred.Experience with deployment of code in distributed environments, cloud application development, and RESTful API-driven architectures.A results-driven "doer", preferably with experience in a high-throughput, rapid-delivery work environment.A problem solver, with an analytical mindset. Proven team player with an ability to work effectively across departments, sites, and time zones.Ability to work independently and contribute in fast-moving start-up environment.

The ranges below reflect the target ranges for a new hire base salary. One is for the Bay Area (within 50 miles of HQ, Palo Alto), the second one (if applicable) is for elsewhere in the US (beyond 50 miles of HQ, Palo Alto). If there is only one range, it is for the specific location of where the position will be located. Actual compensation may vary outside of these ranges and is dependent on various factors including but not limited to a candidate's qualifications including relevant education and training, competencies, experience, geographic location, and business needs. Base pay is only one part of the total compensation package. Full time roles are eligible for equity and benefits. Base pay is subject to change and may be modified in the future. U.S. Base Pay Range $140,000-$160,000 USD Bay Area Pay Range $170,000-$185,000 USD

PsiQuantum's mission is to build the first useful quantum computers-machines capable of delivering the breakthroughs the field has long promised. Since our founding in 2016, our singular focus has been to build and deploy million-qubit, fault-tolerant quantum systems. Quantum computers harness the laws of quantum mechanics to solve problems that even the most advanced supercomputers or AI systems will never reach. Their impact will span energy, pharmaceuticals, finance, agriculture, transportation, materials, and other foundational industries. Our architecture and approach is based on silicon photonics. By leveraging the advanced semiconductor manufacturing industry-including partners like GlobalFoundries-we use the same high-volume processes that already produce billions of chips for telecom and consumer electronics. Photonics offers natural advantages for scale: photons don't feel heat, are immune to electromagnetic interference, and integrate with existing cryogenic cooling and standard fiber-optic infrastructure. In 2024, PsiQuantum announced government-funded projects to support the build-out of our first utility-scale quantum computers in Brisbane, Australia, and Chicago, Illinois. These initiatives reflect a growing recognition that quantum computing will be strategically and economically defining-and that now is the time to scale. PsiQuantum also develops the algorithms and software needed to make these systems commercially valuable. Our application, software, and industry teams work directly with leading Fortune 500 companies-including Lockheed Martin, Mercedes-Benz, Boehringer Ingelheim, and Mitsubishi Chemical-to prepare quantum solutions for real-world impact. Quantum computing is not an extension of classical computing. It represents a fundamental shift-and a path to mastering challenges that cannot be solved any other way. The potential is enormous, and we have a clear path to make it real.