Senior Software Engineer - Mobile (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.

Become a part of our mission and learn more about our Product & Tech team!

We're building the Installation Manager: the mobile app our field teams rely on to digitize everything from ground operations to rooftop installations. As the business scales, more and more depends on this app working beautifully. That's where you come in.

You'll join a cross-functional team of frontend, backend, product, and design folks, and help shape a self-organized group that owns what it builds end to end. We work remotely (Germany-wide), async by default, with offices in Hamburg, Berlin, and Munich if you like one.

A note on our stack: the app is built in Flutter. You don't need prior Flutter experience. If you've shipped and maintained quality mobile apps on any stack and you're excited to go deep on Flutter, we want to talk. We care far more about how you think, ship, and raise the bar for the people around you.

What you'll do:

• Shape the technical direction of the Installation Manager: architecture, release quality, performance, and long-term maintainability
• Ship reliable, well-tested mobile features and help the team build a strong automated-testing and continuous-release practice
• Mentor and grow the engineers around you, sharing what you know across team boundaries (not just within your own role)
• Work closely with product, design, and backend to turn real field feedback into a better product
• Help debug the messy, interesting problems that come with hardware-connected apps in the real world

Technologies and tools you'll work with: Flutter, Patrol, Firestore, GCP (Pub/Sub, Cloud Functions), GitHub, Linear, Miro, and ShapeUp.

What we're looking for:

• Solid experience building, shipping, and maintaining mobile apps in production (any stack; Flutter not required)
• A genuine testing mindset: you've built or driven automated testing and continuous delivery
• You communicate openly and proactively, and you thrive in a remote, async team
• You lift the people around you, and you care about the craft as much as the outcome
• Good spoken and written English

Nice to have (truly optional, please apply without these):

• Flutter, or other cross-platform mobile experience
• Experience building for non digital-native users (our users are out in the field, not at a desk)
• Cloud / DevOps experience, ideally Google Cloud
• API design experience, or breadth beyond mobile (backend, frontend, infra)
• Interest in climate tech

We're building a diverse team on purpose. We welcome applications from people of every background, gender, age, origin, religion, disability, or identity. If you're excited about this role but don't tick every box, please apply anyway, we'd rather hear from you. Need any accommodation during the process? Just tell us, and we'll make it work.