Firmware Engineer (Zigbee Specialist)

IMI plc

We are a global specialist engineering company that creates breakthrough solutions. We are curious and like to solve problems, partnering with our customers to solve the demands of today and prepare for the challenges of tomorrow. We embrace innovation and care about outcomes that are good for business, everyday life and making a better world – creating lasting impact for everyone.

We design, build and service highly engineered products in fluid and motion control applications. We focus on five market sectors: Industrial Automation, Process Automation, Climate Control, Life Science and Fluid Control, and Transport.

Our partnership approach breaks through problems and reduces complexity. We don’t invent in isolation – we collaborate with our customers. We listen closely and we think differently, creating space for diverse minds to innovate. We are working together to make businesses safer, more sustainable and more productive.

Role Overview: We are looking for a Firmware Engineer (Zigbee Specialist) to support our Heatmiser business within IMI Climate Control. As a Firmware Engineer, you will play a crucial role in developing and implementing software for industry-specific hardware. Your expertise will contribute to the success of a cutting-edge product, contributing to the future development of the Company to deliver on our growth strategy. 

Key Responsibilities:

• Design, develop, code, test, and debug high-quality, reliable embedded firmware in C/C++ for microcontroller-based heating control products


• Implement, integrate, configure, and optimise Zigbee 3.0 (and potentially related standards like Green Power) stacks and application layer profiles (e.g., Home Automation) on target hardware platforms


• Focus on ensuring robust, low-power, and standards-compliant Zigbee communication, including mesh networking behaviour, device pairing, security, and interoperability


• Utilise debugging tools (debuggers, logic analysers, oscilloscopes) and protocol analysers (e.g., Wireshark) to troubleshoot complex firmware and communication issues. Develop and execute comprehensive unit, integration, and system test plans, particularly for Zigbee functionality


• Collaborate closely with hardware engineers during the design phase, participate in board bring-up, and develop low-level drivers for peripherals (sensors, actuators, displays, memory, communication interfaces like I2C, SPI, UART)


• Optimise firmware for performance, memory usage, and power consumption, especially critical for battery-powered devices


• Create and maintain clear and concise technical documentation, including design specifications, API definitions, test procedures, and release notes


• Participate in peer code reviews to ensure high code quality, adherence to coding standards, and knowledge sharing


• Stay up-to-date with the latest Zigbee specifications and contribute to ensuring products meet relevant certification requirements (e.g., Zigbee Alliance, UKCA, CE)


• Work effectively within the multi-disciplinary R&D team (Hardware, Software, QA) and potentially with external partners

Critical Competencies for Success:

• Bachelor's degree in Electronic Engineering, Computer Engineering, Computer Science, or a closely related field (or equivalent industry experience)


• Proven commercial experience (ideally 4+ years) in embedded firmware development using C/C++


• Essential Zigbee Expertise: Demonstrable hands-on experience developing firmware for Zigbee-enabled products. Strong understanding of the Zigbee protocol stack (including network, security, and application layers), mesh networking principles, and standard application profiles (e.g., ZHA, ZLL)


• Proficiency with embedded development toolchains (compilers, linkers, debuggers)


• Experience with standard hardware debugging tools and protocol analysers


• Familiarity with version control systems (e.g., Git)


• Experience with specific Zigbee stacks (e.g., Silicon Labs EmberZNet / Gecko)

Desirable Qualifications and Experience:

• Experience developing firmware for low-power, battery-operated devices


• Experience with other wireless communication protocols (e.g., Bluetooth LE, Wi-Fi, Thread)


• Familiarity with test automation frameworks for embedded systems


• Experience in the HVAC, smart home, building automation, or IoT industries


• Understanding of secure coding practices for embedded systems


• Experience with scripting languages (e.g., Python) for test or build automation.

Health & Safety

The physical demands described within the Key Duties & Responsibilities section of this job description are required to perform the essential functions of this position.  Reasonable accommodations may be made for individuals with disabilities.  Please contact your local HR representative to discuss the specific Work Conditions and Physical Requirements of this role.  

Health, Safety, and Environmental Duties – At IMI, we are all personally committed to protecting our people, minimising our impact on the environment, the communities we operate in and our company. All members of our workforce have the duty to ensure the health, safety and welfare of themselves, others, and the environment. Every employee is expected to follow all HSE operating procedures, also to challenge any observed behaviours or unsafe acts.

Code of Ethics

IMI requires the highest standard of ethics in all business dealings, particularly with customers, suppliers, advisors, employees, and the authorities. In accordance with the IMI Way: Our Code of Responsible Business.

Changes to This Job Description

IMI may amend this job description in whole or in part at any time.

IMI is an equal opportunity employer. Qualified applicants will be considered without regard to age, race, creed, colour, national origin, ancestry, marital status, affectional or sexual orientation, gender identity or expression, disability, nationality, sex, or veteran status.