Embedded Software Engineer, Electric Floor Heating

OJ Electronics; Sønderborg; On-site; DKK 520,000 - 600,000; Full time

Benefits offered by this job

Flat structure

Growth opportunities

Friendly culture

High employee satisfaction

Job summary

OJ Electronics in Sønderborg, Denmark, seeks an embedded software engineer to join our R&D team. You will help develop real-time embedded systems that control our energy-efficient heating solutions and collaborate across software, hardware, and cloud-based areas.

You will contribute to full product lifecycles, work with display technologies and wireless protocols, and support system design with an agile mindset. On-site presence in Sønderborg is required.

Qualifications

• 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 and schematics.
• Experience with version control (Git + Git Flow) and CI/CD.
• Basic knowledge of communication protocols (UART, I2C, SPI).
• Structured problem-solving and debugging skills.
• Clear and concise technical communication in English.
• Team-oriented and agile collaboration experience.
• Independence and accountability; on-site presence in Sønderborg is required.

Responsibilities

• 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).
• Participate in agile ceremonies and code reviews.

Skills

Embedded C/C++ for embedded

Microcontrollers

RTOS

Debugging

Version control

CI/CD

English communication

Agile

Teamwork

On-site readiness

Tools

Git

Git Flow

CI/CD tools

Job description

Last updated: 18-08-2026 06:10:07

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

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.

Read more 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. Due to the summer holidays we expect to start interviewing mid to late August.

About OJ Electronics

Founded in 1964 and headquartered in Sønderborg, Denmark, OJ Electronics produces electronic controls for underfloor heating and HVAC controls and drives. Our products are available through partners and distributors worldwide, and we have subsidiaries and sales offices in key markets, including the United States and Poland. Everywhere, we are known for our innovative approach, insistence on product quality, and deep application knowledge – all of which helps customers differentiate themselves in the market.

In June 2023, OJ Electronics was acquired by BITZER Electronics, a BITZER Group company also headquartered in Sønderborg. This makes OJ Electronics part of the BITZER Group family, which is represented at 75 locations in over 40 countries and employs some 4300 people worldwide, 185 in OJ Electronics, Sønderborg, Denmark.