Solutions Architect (Quantum-Secure Networks) - all genders

Location: Vienna HQ, with customer travel across DACH/EU · Reports to: Head of Sales Languages: German and English (fluent) About zerothird

At zerothird (zerothird.com), we’re building the next generation of secure communications.

As a fast-growing quantum technology company, we develop entanglement-based Quantum Key Distribution (eQKD) systems - enabling a new standard of security that is fundamentally resilient against both current and future (quantum) cyber threats.

Our technology builds on decades of pioneering quantum research and is designed to protect the networks of critical infrastructure, telecom providers, and enterprises worldwide.

Joining zerothird means turning quantum science into real-world security - and helping define how global communication stays protected in the quantum era. The role

The Solutions Architect is the technical authority in front of customers and the person who brings projects over the line. The role exists to earn the technical win: translating customer requirements into credible, production-grade eQKD and QKaaS network designs, integrating quantum key delivery with classical security and telecom infrastructure, and giving conservative technical buyers the confidence to commit.

It is also the field-to-R&D conduit - the patterns you see in the field shape the roadmap. You sit inside the deal team with Account Executives, supply Marketing with technically accurate product input, and give the GTM & Partnerships Manager the foundations for partner certification., * Architecture & design: turn customer requirements into scalable, secure eQKD/QKaaS network designs, reference architectures, and integration blueprints (with classical IT security and telecom infrastructure - PKI, VPN, SD-WAN, encryption layers, routing).

• Technical win: lead technical workshops and validation sessions with CISOs, network architects, and system integrators; own POCs end to end (e.g. inter-datacenter and inter-city link deployments).
• Deal support: partner with the Account Executives to provide technical authority throughout the cycle; author technical proposals, architecture documentation, and responses to RFPs and security questionnaires.
• Partner enablement: produce the reference architectures and integration patterns the GTM & Partnerships Manager needs to certify hosting and service-provider partners for QKaaS delivery.
• Roadmap feedback loop: capture field requirements, identify patterns across use cases, and work with product and R&D to prioritize what real deployments need., * The role of technical authority on the most advanced deployments in quantum-secure communications, working directly with customers and partners.
• A first-year mandate to produce reusable reference architectures, convert at least one production-grade POC toward commercial rollout, and measurably influence the product roadmap.
• A collaborative, high-trust engineering culture with a genuine field-to-R&D loop - your input shapes what gets built.
• Work at the intersection of Nobel Prize-winning quantum physics and secure communications, helping protect global infrastructure for decades.
• Vienna HQ with flexible, family-friendly arrangements, tailored onboarding, and a dedicated mentor.

• 6+ years in solutions architecture, technical pre-sales, or systems engineering for complex infrastructure, security, or networking products.
• A strong command of enterprise networking and IT security architecture; working knowledge of cryptographic concepts and secure-communication design principles.
• A proven ability to design and defend integration architectures in front of demanding technical buyers, and to simplify complexity for mixed business/technical audiences.
• A track record delivering POCs and multi-party technical projects with integrators and customer engineering teams.
• Exposure to critical infrastructure, telecom, or public-sector environments.
• Fluent German and English.
• Nice to have: familiarity with QKD / quantum-secure communications (or the ability to ramp fast on new physical-layer technology); experience integrating with carrier or datacenter network platforms (e.g. Cisco routing/optical, key-management systems); experience contributing to product roadmaps from field input.

The minimum gross salary for this position is €3.806,97 per month (x14, based on full-time employment) in accordance with the applicable collective agreement, plus a performance-based bonus. However, there is a willingness to offer a higher salary depending on experience and qualifications.