Principal Software Engineer (m/f/d)

At 1KOMMA5°, we pursue a clear vision: Living on wind and sunlight forever for free. To make this a reality, we are building the energy system of the future with Heartbeat AI. Want to be part of it?
We bring together regional craftsmanship and scalable software: We don't think of solar, batteries, heat pumps, and e-mobility as isolated components, but control them as an intelligent, integrated overall system in our virtual power plant. Directly connected to the electricity market – in real time, fully automated. This way, energy is used when it is available from renewables and particularly cost-effective. By 2030, our goal is to transition 1.5 million households to renewable energies. Over 3,000 people are working towards this every day, at more than 80 locations worldwide, from Finland to Australia.

Want to take responsibility and build solutions that truly matter? Apply now and help us shape the energy world of tomorrow.

Learn about our Product & Tech team!

In tech we have two main work streams:

• Heartbeat: Building a virtual power plant levering our energy manager “Heartbeat” and evolving the customer experience app around this
• Operating System for installation companies: Digitisation of operations and processes from ground operations to rooftop installations At 1KOMMA5°, we are looking for a top-tier Principal Software Engineer who leads with clarity, decisiveness, and deep technical insight. You will shape and own critical architectural decisions, drive alignment across teams, and ensure execution at the highest technical standard.

• Shape the organisation's technical strategy and innovation efforts
• Accountable for consistent execution of technical decisions by setting clear direction and holding teams accountable for implementation
• Ensure continuously that our software architecture is shaped in close alignment with product management to support current and future product direction
• Lead architectural direction to enable the delivery of scalable, maintainable, and state-of-the-art solutions
• Translate business requirements into technical solutions
• Tackle and resolve deep technical challenges with urgency and precision
• Mentor and challenge engineers to accelerate their professional growth
• Build and scale a high-performance tech organisation and engineering culture

• Typescript/JavaScript/NodeJS (VueJS/NestJS)
• Ruby on Rails
• Flutter (Dart)
• Google Cloud Platform
• Terraform
• GitHub Actions
• IoT applications

You have:

• Extensive hands-on experience in software development with multiple general-purpose programming languages for a minimum of 5 years
• A proven track record of architecting scalable and secure systems, demonstrating a strong commitment to quality
• Extensive experience in designing and implementing APIs that enable seamless integration and system communication
• An agile and result-oriented mindset, with a strong emphasis on collaboration and teamwork
• Expertise in communicating with stakeholders in business terms and understanding the technical implications of their requirements
• Industry-leading experience driving cross-functional teams and enforcing engineering alignment in fast-paced environments, including making and following through on critical technical decisions
• Excellent verbal and written communication skills in English, with proficiency in German considered a plus Bonus points for:
• Experience with IaC (ideally Terraform)
• Interest in climate tech industry We are an ambitious and dynamic company with a talented team. We require our engineers to be imaginative, enthusiastic, and willing to tackle new challenges as we strive to provide everyone with renewable energy technologies.

• You are part of an international, dynamic, and highly motivated team of people who have proven to make things happen
• With your work, you accelerate the "energy transition" and hence have a direct impact on our climate
• Work with and learn from other super-smart colleagues
• You will enjoy direct contact with core decision-makers
• You will enjoy the best chances of entering full-time in one of Europe’s most thriving scaleups
• You work remotely (Germany-wide), with offices in Hamburg, Berlin or Munich
• Create a healthy balance alongside your work and enjoy all the benefits of the EGYM Wellpass
• Benefits and discounts are yours with Futurebens
• Whether city bike or e-bike - be flexible with our job bike leasing and do something good for the environment at the same time
• Individualised opportunities for professional development
• Reporting directly to the CTO

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