[Remote] (Senior) Full-Stack Software Engineer - Financial Infrastructure & Payments (m/f/d)
Note: The job is a remote job and is open to candidates in USA. 1KOMMA5° is a CleanTech Unicorn on a mission to electrify everything and connect everyone to the future energy market through their AI-based software platform, Heartbeat AI. They are seeking a Senior Full-Stack Software Engineer to design and run billing, invoicing, and monetization systems that support the global energy transition, ensuring scalability, reliability, and performance while collaborating with various teams.
Responsibilities
- Contribute as a Full-stack engineer within a team of self-driven software developers
- Design, build, and maintain business-critical systems across the stack. From scalable backend services and APIs to performant, user-friendly frontends with reliable flows for invoices, payments, and subscriptions where they touch customers and finance
- Partner with finance, operations, and product to translate complex, loosely defined billing requirements into clear, actionable technical solutions, including compliance-minded documents and audit-friendly reporting where needed
- Own slices of the invoice lifecycle (generation, delivery, and archival), templating and localization, and reconciliation and reporting together with stakeholders
- Champion clean architecture, component reusability, and maintainable UI patterns using modern frameworks (e.g. React, Next.js, or similar)
- Drive experiment-driven innovation and uphold strong engineering practices in testing, CI/CD, observability, and code quality
- Continuously improve developer experience by reducing technical debt, automating workflows, and documenting key decisions and operational processes
- Operate effectively in an asynchronous, outcome-oriented environment, managing your work autonomously and maintaining clear communication through documentation and structured updates
- Contribute to lightweight project management by defining milestones, ensuring technical feasibility, and aligning engineering work with product goals
Skills
- Experience writing maintainable, reusable, and testable code in TypeScript, with strong skills in both frontend frameworks and backend technologies
- Strong understanding of API design, data modeling, and system integration (RESTful or GraphQL), including patterns for idempotent money movement and auditable billing events where relevant
- Proven ability to own features end-to-end, from UX and architecture to deployment and monitoring
- A pragmatic, product-focused mindset that balances technical excellence with delivering customer value for regulated or finance-adjacent flows
- Curiosity and initiative to explore new tools and methods that improve product quality and engineering efficiency
- Excellent written and spoken English (German is a plus)
- Residency in Germany
Benefits
- 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 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
Company Overview