Co-founder & CTO / Technical Lead — Passive Radar & Sensing

Build the eyes for the airspace nobody currently sees. About Fravek Fravek is developing a new generation of passive radar technology for drone detection and low-altitude airspace awareness. By using existing radio signals in the environment instead of transmitting our own, we aim to detect and track aerial threats while remaining electronically silent. Our mission is to build the missing layer of airspace awareness — protecting critical infrastructure, defence operations and the environments that matter most. We are an early-stage Swedish deep-tech company, already working with experienced radar and signal-processing partners and pursuing field validation with operational partners, including in Ukraine. Now we're looking for someone exceptional to help build the technology — and potentially the company itself. The opportunity We are looking for a Co-founder & CTO / Technical Lead who combines deep technical understanding with hands-on engineering capability and an entrepreneurial mindset. Someone who gets excited when mathematics becomes a signal on an SDR — and when that signal becomes a track on a screen. You will take technical ownership of Fravek's development, from experimental prototypes to operational sensing systems. This is not a traditional management-only CTO role. We need someone who can architect systems, write code, challenge algorithms, troubleshoot hardware and lead other engineers. For the right person, this offers a potential co-founder role with meaningful equity participation and the opportunity to shape our technology, team and company from an early stage. What you will do Lead the technology

• Define the technical architecture and development roadmap for distributed passive radar systems.
• Make critical engineering decisions across RF hardware, DSP, embedded compute, software and sensing infrastructure.
• Translate research and prototypes into robust, field-deployable systems.

Build and validate

• Work hands-on with SDR receivers, RF front ends, antennas and multi-channel acquisition.
• Develop and improve correlation, Doppler processing, clutter suppression, detection, localisation and target tracking.
• Integrate algorithms into real-time software and hardware platforms.
• Design measurable, repeatable experiments and validate performance through field testing.

Build the engineering capability

• Recruit, mentor and lead a small, highly capable technical team.
• Collaborate with external radar experts, research institutions and development partners.
• Establish engineering standards for testing, documentation, performance and reliability.

Connect technology with real-world needs

• Work closely with founders, customers and operational partners.
• Translate field observations and customer requirements into technical priorities.
• Contribute to technical demonstrations, partner evaluations and strategic technology decisions.

Who we're looking for You might come from radar, telecommunications, electronic warfare, radio astronomy, GNSS, acoustics, SDR or another advanced sensing field. We believe you will bring:

• A strong foundation in mathematics, physics and digital signal processing.
• Practical experience with RF systems, SDR hardware and real-world signal acquisition.
• Excellent programming capability in Python and/or C/C++.
• Experience taking algorithms beyond simulation into working systems.
• An understanding of systems engineering, hardware/software integration and experimental validation.
• The ability to make sound technical decisions under uncertainty.
• Curiosity, initiative and a genuine enjoyment of solving difficult engineering problems.
• The communication and leadership skills to help build a team and collaborate with technical and non-technical stakeholders.

- Experience with passive or bistatic/multistatic radar, array processing, FPGA/GPU acceleration, synchronisation, sensor fusion, GNSS, electronic warfare or real-time embedded systems is highly valuable. A relevant technical degree is welcome, but demonstrated ability and practical experience matter more. Who you are We are not necessarily looking for someone who has already been a CTO. You might be a senior radar engineer ready to lead. A DSP specialist with exceptional systems thinking. A technical founder looking for the next challenge. Or an accomplished researcher who wants to build technology that works outside the laboratory. What matters most is the combination of brains, hands, curiosity and ownership. You are comfortable moving between the whiteboard, the code editor, the laboratory and the field. You want to build a company, not just a technology. What we offer

• A potential Co-founder & CTO position with meaningful equity participation.
• Substantial influence over architecture, engineering decisions and technical strategy.
• Collaboration with experienced radar, RF and signal-processing specialists.
• The opportunity to build a world-class sensing team.
• Direct involvement in real-world testing and operational validation.
• A mission-driven deep-tech environment with ambitious international potential.

Location: Stockholm, Sweden. Hands-on collaboration and field testing are important; working arrangements can be discussed. Let's talk. You don't need to know everything about radar. But you should want to become exceptionally good at it — and help build something that matters.