Use your embedded SW development skills to make our incredible thermostats even better!

Apply before: as soon as possible | Last updated: 31-07-2025 13:02:17

Embedded software developer looking for new challenges at an industry-leading company? Want to work with a skilled R&D team to keep advancing our successful thermostats for underfloor heating systems? Keen on working for a smaller company, where your work really matters every day? Then please read on and tap “Apply” below.

Read more Apply OJ Electronics, a global producer of underfloor heating solutions and HVAC drives and controllers, is looking for an embedded software engineer to join our impressive and highly diverse R&D department.

Working with skilled and experienced colleagues in software development, hardware development and cloud-based solutions, your main job will be to help develop real-time embedded systems that control our energy-efficient heating solutions.

You will be involved throughout the product lifecycle, from initial idea to shipped firmware. And your day-to-day work will involve tackling challenges in areas as diverse as wireless communication, home automation protocols, display technologies and control-system engineering.

Your role
Reporting directly to our R&D development manager, you’ll be expected to:

• Develop embedded C/C++ code for microcontrollers
• Integrate software with custom hardware
• Contribute to system design and architecture
• Maintain code quality through testing and refactoring (unit and integration tests)
• Contribute to system design and architecture
• Participate in agile ceremonies and code reviews

Our expectations
When reviewing your application, we will look for:

• Proficiency in C/C++ for embedded systems
• At least three years of work-experience in embedded software development
• Experience with microcontrollers and real-time programming (Free RTOS and/or “bare metal”)
• Familiarity with embedded debugging tools (e.g., oscilloscopes, JTAG)
• Understanding of hardware/software interfaces
• Ability to read and interpret schematics and datasheets
• Experience with version control (Git + Git Flow) and CI/CD
• Basic knowledge of communication protocols (e.g., UART, I2C, SPI)
• Structured problem-solving and debugging skills
• Clear and concise technical communication (in English)
• Team-oriented mindset and agile collaboration experience
• Independence, accountability, and a friendly demeanor
• A willingness to work on-site from our office in Sønderborg. A remote or hybrid setup is not possible for this job.

In addition, useful skills include:

• Experience with embedded display technologies (e.g. TFT, LCD)
• Familiarity with touch interfaces (capacitive/resistive)
• Experience with UI frameworks for embedded systems and optimizing UI/UX for embedded systems with limited resources
• Driver development for display controllers and touch sensors
• Development with wireless protocols such as Wi-Fi and Bluetooth Low Energy (BLE)
• Understanding of Apple HomeKit (AHK) integration and certification flows
• Knowledge of Matter (Connectivity Standards Alliance) and smart home integration
• Knowledge about security for embedded systems

Working at OJ
Looking for a company where you matter every day? At OJ, you’ll find:

• A flat organizational structure where decisions are implemented quickly
• Opportunities to grow by taking on greater responsibility over time
• An informal, friendly and open workplace culture
• An employee satisfaction score over 80 for several years running

Note that this position requires a day-to-day physical presence at our offices in Sønderborg, Denmark.

The application process
For this position, we will be interviewing on an ongoing basis until we find the right person.

Apply