PaiDefence

PaiDefence is a British-Ukrainian DefenseTech company building air defence systems already deployed on the frontlines. We push real technology to the battlefield — not demos, not paper specs.

We are looking for a Lead Hardware & Systems Engineer to own the full hardware domain — from system architecture through to serial production and stable field operation. You will drive our prototype to a production-ready device, coordinate mechanical and electronics engineers, and set up small-series manufacturing with potential to scale.

Responsibilities

• Architecture & Design — system hardware architecture, component and enclosure selection, thermal management, sealing, rugged design decisions, and technical specifications
• Hands-on Development — hardware bring-up, testing, verification, reliability analysis, and fault investigation
• Industrial Readiness — prototype-to-DFM/DFA transition, production documentation, contractor management, and quality control

• System Integration — integration of hardware with electronics, sensors, and antenna systems; cable architecture; field power; uptime and health monitoring

   

Requirements

• Proven experience in hardware system development
• Track record of taking a product from prototype to serial production
• Strong system architecture skills and hands-on hardware development
• Familiarity with industrial-grade or mil-tech standards

• Understanding of mechanical design and CAD tools

   

Nice to Have

• Experience with rugged solutions for field or industrial environments
• Background in DefenseTech, aerospace, or adjacent domains
• Familiarity with RF components or antenna systems

• English — B1+ (technical documentation, occasional communication)

   

What We Offer

• Real impact — your decisions directly affect the reliability of air defence systems in the field
• Full ownership of the hardware domain from day one
• Deep-tech engineering challenges that don’t exist in the civilian sector
• Office in central Kyiv, 3 minutes from the metro
• Full-time, standard business hours; some tasks may require involvement outside the usual schedule (field testing, critical updates)

PaiDefence is a British-Ukrainian DefenseTech company building air defence systems already deployed on the frontlines. We push real technology to the battlefield — not demos, not paper specs.

Our core value is impact for Ukraine: we build technology that makes a real difference where it matters most. We operate with a deep-tech mindset, pushing engineering rigour into every product we ship. We value ownership and responsibility — people who execute, deliver, and stand behind their results.

We are looking for an RF Engineer to join our hardware team and work on the radio frequency subsystems of our detection and countermeasure products. You will work directly with signals, hardware, and real measurement data — not simulations.

Responsibilities

• Analysis and improvement of RF signal paths in direction-finding and detection systems
• Component selection, datasheet review, BOM compilation, manufacturing/assembly requirements
• RF measurements and prototype testing: S-parameters, VSWR, insertion loss, linearity, spurious/harmonics
• Troubleshooting RF system issues: impedance mismatch, nonlinearity, losses, EMI/EMC, stability
• Design optimization for efficiency, size reduction, cost, and power consumption
• Preparation of technical reports, documentation, and specifications

Requirements

• Hands-on experience designing RF systems
• Deep understanding of transmission lines, wave propagation, S-parameters, impedance matching, active and passive RF components
• Practical experience with RF circuit design
• Hands-on experience with SDR (Software-Defined Radio)
• Proficiency with lab equipment: VNA, spectrum analyzer, oscilloscope
• Skills in diagnosing and resolving RF performance issues: EMI/EMC, instability, self-oscillation, spec non-compliance
• English — reading technical documentation

What We Offer

• Real impact — your work goes directly into systems protecting Ukrainian forces on the frontline
• Work within a senior engineering team — direct, senior-to-senior communication with minimal overhead
• Hands-on deep-tech environment with actual hardware, real signals, and real field feedback
• High ownership — direct influence on technical decisions and product direction
• Office in central Kyiv, 3 min from the metro
• Full-time, standard business hours

We are a British—Ukrainian air defence tech company building distributed systems across the frontline. We are looking for a Founding Engineer with deep expertise in Machine Learning and Computer Vision to take full ownership of the architecture and implementation of detection systems for our current and future product lines.

Our core value is impact for Ukraine: we build technology that makes a real difference on the actual battlefield, not in labs or on paper specs. We operate with a deep-tech mindset, pushing new technologies where engineering rigor truly matters. We value ownership and responsibility—people who execute, deliver, and stand behind the results.

We especially value engineers with strong analytical thinking and proven problem-solving skills — such as participation in mathematical/programming olympiads or experience contributing to open-source projects.

Key Responsibilities

• Detection Systems Development: Build and maintain the full lifecycle of ML solutions across the company’s product lines.
• Inference Engineering: Optimize models for real-time operations.
• Backlog Execution & Implementation:
  • Develop RF Classification models (Radio Frequency signals).
  • Improve the accuracy of DoA (Direction of Arrival) algorithms.
  • Implement drone behavior analysis and pilot localization algorithms.
• Best Practices: Define the architecture, tooling, and approaches to build a scalable ML infrastructure from the ground up.

Skills & Requirements

• Strong theoretical background in Linear Algebra, Probability, and Statistics.
• Experience with Computer Vision models: Classification, Object Recognition, and Tracking.
• Python + relevant ML libraries, PyTorch.
• Experience taking models to production (Production ML).
• Hands-on experience with inference engines.
• Ability to build low-latency, real-time detection pipelines.
• Proficiency in C++ and/or CUDA for building high-performance modules.

Nice to Have

• Experience in DefenseTech, SigInt (Signals Intelligence), or Embedded Systems.
• Understanding of Radio Frequency (RF) physics.

We Offer

• Meaningful and high-impact work in the AIR defense domain
• Practical R&D environment with real autonomy
• Direct influence on technical decisions and the product direction
• Work in an experienced senior engineering team
• Сlear, fast, senior-to-senior communication with a minimum number of team meetings
• Office in the center of Kyiv (available for onsite work when required)
• Full-time position
• Standard business hours; some tasks may require involvement outside the usual schedule (testing, critical updates)

Paidefence is a British-Ukrainian air defence tech company building distributed systems across the frontline. Our core value is impact for Ukraine: we build technology that makes a real difference on the actual battlefield, not in labs or on paper specs. We operate with a deep-tech mindset, pushing new technologies where engineering rigor truly matters.

We’re looking for an experienced Linux engineer whose primary responsibility will be integrating various SDR (Software Defined Radio) devices into our software platform. This is a role for those who love working at the hardware-software boundary, understand how data travels from physical ports to high-level applications, and can make that path as fast and reliable as possible.

What you’ll do:

• Integrate different SDR models into a unified Linux-based ecosystem
• Work with vendor SDKs and develop high-performance userspace applications
• Optimize high-throughput data processing in real-time
• Write clean, stable, and performant code in C++ or Python
• Debug inter-process communication, manage buffering and latency

Requirements:

• 5+ years of professional Linux systems experience
• Linux Power User: comfortable in terminal, understands kernel-space vs user-space, knows systemd and driver configuration
• Hardware Interface Expert: hands-on experience with USB 2.0/3.0, Ethernet, or other high-throughput interfaces
• Data Stream Architect: understands IPC principles, ring buffers, memory overflow prevention, and latency minimization for raw data transmission
• C++ Developer: writes reliable code that doesn’t crash on the first unexpected packet from hardware
• English: B2 or higher

Nice to have:

• SDR experience: familiar with RTL-SDR, HackRF, USRP, or has GNU Radio experience
• Experience with ROS/ROS2 (node development, topics/services)
• Understanding of data transmission protocols and digital signal processing (DSP)
• Hobbies related to electronics, radio communication, or robotics

We offer:

• Meaningful, high-impact work in Ukraine’s air defense domain
• Deep-tech engineering challenges where rigor and performance matter
• High ownership and autonomy from day one
• Work format: Kyiv office with occasional remote days
• Senior engineering team with direct communication and minimal bureaucracy
• Full-time position with standard hours; occasional off-hours for testing/updates