Principal Engineer - Classical Cryptography & Architecture

IonQ, Inc. [NYSE: IONQ] is the world’s leading quantum platform and merchant supplier - delivering integrated quantum solutions across computing, networking, sensing, and security. IonQ’s newest generation of quantum computers, the IonQ Tempo, is the latest in a line of cutting-edge systems that have been helping customers and partners including Amazon Web Services, and AstraZeneca achieve 20x performance results and accelerate innovation in drug discovery, materials science, financial modeling, logistics, cybersecurity, and defense. In 2025, the company achieved 99.99% two-qubit gate fidelity, setting a world record in quantum computing performance.

Headquartered in College Park, Maryland, IonQ has operations in California, Colorado, Massachusetts, Tennessee, Washington, Italy, South Korea, Sweden, Switzerland, Canada, and the United Kingdom. Our quantum computing services are available through all major cloud providers, while we also meet the needs of networking and sensing customers across land, sea, air, and space. IonQ is making quantum platforms more accessible and impactful than ever before.  

We are looking for a Principal Engineer to own the classical cryptography architecture of our post-quantum cryptography (PQC) hardware acceleration products, targeting hardware security module (HSM) and network-appliance applications. Real-world quantum-safe systems are hybrid systems: classical and post-quantum algorithms operating side by side, with careful key management, crypto agility and migration paths. You will be the senior authority for this classical and hybrid layer, working alongside our PQC architecture leadership. The role demands fluency on both sides of the transition: deep classical mastery combined with a solid working command of the post-quantum algorithms and standards the products are built around.

We are looking for a candidate with a Master’s or PhD in Cryptography, Computer Science, Electrical Engineering or a related field and at least twelve years of experience implementing and architecting classical cryptography in real products, in hardware, software or both. You have deep command of symmetric and asymmetric primitives, modes of operation, key management and entropy generation, and you have taken cryptographic subsystems through FIPS 140-3 or Common Criteria evaluation. You also bring a solid working knowledge of the NIST post-quantum algorithms (ML-KEM, ML-DSA, SLH-DSA) and their deployment constraints: you do not need to be a lattice specialist, but you must be able to architect hybrid schemes with one.

You understand the practical constraints of deployed security infrastructure (HSMs, PKI, TLS and IPsec ecosystems) and how hybrid classical/post-quantum schemes are standardised and deployed in practice. You write precise specifications, guide implementers effectively, and make sound architecture decisions under real-world interoperability constraints. Fluency in English is required; French or German is an advantage.

• →Proven architect of classical cryptographic subsystems with certification experience (FIPS 140-3, CAVP, Common Criteria)
• →Practical knowledge of hybrid classical/PQC schemes, crypto agility and key-management architecture, with working command of the NIST PQC standards

You believe that quantum-safe security is only as strong as the classical foundations it stands on. You enjoy being the guardian of correctness and interoperability in a programme pushing new technology, and you take pride in migrations that customers barely notice because they simply work.