Salary: £33,000 - 60,000 per year Requirements: We are looking for strong professional experience writing embedded software in C and C++. We want a solid understanding of low-level systems, including registers, interrupts, DMA, memory mapping, timing constraints, and peripheral configuration. We need practical experience with RTOS concepts such as tasks, queues, semaphores, mutexes, stack limits, scheduling, and resource ownership. We expect a clear commitment to writing clean, readable, maintainable, and testable code. We need comfort debugging physical hardware using tools such as oscilloscopes, logic analysers, serial consoles, and schematics. We value a genuine passion for technology, embedded systems, and building products that work in the real world. We want a collaborative, practical mindset suited to a fast-moving multidisciplinary startup. Bonus experience in RISC-V architectures or custom compiler toolchains is valuable. Bonus experience with the Embedded Template Library or allocation-aware C++ development is valuable. Bonus experience with FreeRTOS on production devices is valuable. Bonus experience with embedded networking protocols such as TCP/IP, Wi-Fi, HTTP, MQTT, TLS, or AWS IoT is valuable. Bonus experience with OTA bootloaders, secure update flows, or fail-safe firmware recovery is valuable. Bonus experience with camera sensor interfaces, image capture, ISP pipelines, JPEG/MJPEG encoding, or image processing is valuable. Bonus experience deploying quantised machine learning models using TensorFlow Lite Micro, ONNX, or local NPUs is valuable. Bonus experience with STM32, Cortex-M, ESP32, or similar microcontroller platforms is valuable. Bonus experience with consumer electronics, IoT products, or connected devices shipped to real users is valuable. Bonus experience working in small engineering teams where software, electronics, mechanics, and manufacturing overlap is valuable. Responsibilities: We will have you develop and optimise production-grade C and C++ firmware for a dual-core, heterogeneous RISC-V SoC running FreeRTOS. We will have you maintain and expand firmware responsible for Wi-Fi connectivity, secure TCP/IP cloud communication, local e-paper UX rendering, SD/MMC storage, USB interfaces, and over-the-air update flows. We will have you work on high-speed camera capture, hardware-accelerated JPEG encoding, local NPU classification pipelines, and inter-core communication between processing domains. We will have you configure, debug, and maintain interfaces including I2C, SPI, UART, USB, SD/MMC, GPIO, timers, DMA, and other SoC peripherals. We will have you design robust software abstractions suitable for constrained systems, using tools such as the Embedded Template Library to manage fixed-capacity data structures and avoid memory fragmentation. We will have you diagnose issues on real prototypes using oscilloscopes, logic analysers, serial consoles, datasheets, schematics, and careful reasoning. We will have you work closely with our lead electronics engineer and wider hardware team. We will have you help ensure firmware is stable, recoverable, testable, and suitable for real customers using the product every day in unpredictable home environments. We will give you meaningful ownership from day one and expect you to help shape the embedded architecture of our product line. Technologies: AI AWS Cloud Embedded Firmware FreeRTOS Hardware HTTP IoT Machine Learning MQTT TCP/IP TensorFlow UX UI Design C++ LLM Robotics More: We are OnlyCat, a fast-growing smart pet technology company building intelligent, AI-powered products for cat owners around the world. We have grown from a home prototype into a global brand with thousands of smart cat flaps shipped, 4x year-on-year growth, and recognition on BBC Ones Dragons Den. We are now scaling production, deepening our technology stack, and building the next generation of smart pet appliances. You will join a hands-on, collaborative engineering team working across embedded software, electronics, mechanical engineering, product design, AI, and manufacturing. This is an on-site role in our mechatronics lab, giving you direct access to hardware, prototypes, and test equipment. We offer a salary of £33,000–£60,000 depending on experience, EMI share options, on-site and free parking, a company pension, casual dress, and regular company-sponsored social events. last updated 23 week of 2026