Backend Engineer (f​/m​/d

• Proven track record of solving complex bugs, with evidence such as post-mortem, blog post, or PR link.
• Experience in early-stage startup environments (small teams, high autonomy) and the intention for learning new technologies and self-reliance to take responsibility.
• 3–5 years of professional software engineering experience.
• Examples of product ownership from idea to measurable success.
• Active contributions to open-source projects.
• Practical use of AI tools in development.
• Ideally familiarity with IT/OT protocols (MQTT, OPC UA) or Industrial IoT.

• Open-Source Company:
  We’re building UMH Core - an open-source Industrial IoT platform used by factories worldwide. The code you write is public, peer-reviewed, and directly impacts manufacturing operations.
• Professional Growth – Ongoing learning opportunities, room to grow in a scaling company, and direct impact on UMH’s success.
• Fast-Paced Environment:
  Daily release cycles through merge queues with automated tests, staging environment, and then into production with instant feedback from users through Discord or session recordings. Identify an interesting improvement for UMH? Have it live in production in 3-6 hours.
• Value your work:
  Recognition and reward for your work with competitive salary packages, company participation (VSOP), and subsidized memberships (e.g., Urban Sports Club, EGYM Wellpass).
• Modern Workspace:
  Work in a well-equipped, modern office located in the heart of Ehrenfeld (Cologne), flexible working hours, hybrid work.

Build and scale a real-time data platform that runs hundreds of Benthos pipelines inside a single Docker container, processing millions of industrial messages that control actual production processes.

What you will do:

• Industrial-Scale Stream Processing:
  Architect systems handling 50+ protocol converters (OPC UA, Modbus, S7, MQTT) running concurrently in resource-constrained edge environments.
• Unified Namespace Architecture:
  Design APIs and data flows connecting PLCs, sensors, ERP/MES systems into one coherent “Unified Namespace” using Redpanda (Kafka-compatible).
• Edge-to-Cloud Pipeline:
  Build robust data pipelines that survive network outages, buffer locally, and guarantee message delivery for mission-critical factory operations.
• Debug distributed systems issues across industrial protocols, edge devices, and cloud infrastructure.
• Fast shipping with safety nets - PRs to production in 3h-4h through automated testing, code reviews, and staged rollouts.
• Open Source at Scale:
  Contribute to
• Close collaboration with Customer Success and the user community via Discord, Slack, Linear, and Git Hub.
• Technologien:
  Kafka (Redpanda), Docker, S6, fly.io, Grafana, Node-RED, k3s, Helm, Go, Svelte, Typescript.