Stefan Keller from Bavaria
Stefan Keller
I build digital systems that actually run.
From ideas, processes, and requirements I create digital systems that are sustainable and work in everyday operations - cleanly architected and thought through all the way to production.
Latest: Learning platform launched in 2 days - 500+ users in 4 months.
12db.de - from zero to live in 2 days
Independently developed, launched in 2 days, and grown to 500+ users within 4 months.
When I'm the right fit
I'm the right choice when a project needs to be built, not just planned. When processes, data, technology, and operations come together. When you need someone who doesn't just understand, but delivers.
- when a digital project is stuck between idea, requirements, and execution
- when many moving parts need to become a coherent system
- when marketing, recruiting, or operational processes need to work together seamlessly
- when something needs to be not just designed, but actually shipped and operated
System ownership, not isolated disciplines
I take responsibility for the whole - not just individual components.
Process Architecture
Designing workflows that make everyday operations simpler. The tool follows the process - not the other way around.
Automation & Data Flows
Reducing repetitive work, setting up clean data flows, connecting interfaces - stable instead of cobbled together.
Data Models & APIs
Designing structures, managing information cleanly, making systems talk to each other.
Infrastructure & Operations
Building platforms, deploying, monitoring, and operating them - with responsibility across the entire lifecycle.
Product Development
Understanding requirements, designing architecture, building, shipping. Not as theory, but all the way into practice.
Growth & Marketing Systems
Building tracking, reporting, and scalable processes - so marketing becomes measurable instead of guesswork.
Selected Projects
12db.de
Amateur radio training lacked a modern, open learning platform.
Product, architecture, frontend, backend, content, operations - built entirely on my own.
Live system with organic growth, trade press mention, and real usage in a niche market.
Internal AI Platform
Sensitive data, no use of external AI services possible. At the same time, a need for AI support in daily operations.
Conception and setup of a fully local AI platform - LLMs, RAG, SSO, knowledge base. Privacy-compliant, without cloud dependencies.
Internal AI platform built to production readiness - locally operated, privacy-compliant, and tailored to everyday workflows.
Recruiting Platform
Heterogeneous processes, media breaks, little transparency.
Made recruiting centrally manageable - built the platform, processes, and tracking across multiple locations.
Applicant volume tripled, cost per application well below industry benchmark.
Thoughts & Analysis
Technology, infrastructure, systems thinking. Focus on mechanics and execution - substance over opinion.
Side Projects While Working Full-Time. No Secret. Just Focus.
Between a full-time job, family and sleep, there's little time left. How I build projects on the side, what drives me - and how it feeds directly back into my day job.
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Release Speed Without Losing Control
High release frequency signals motion, not maturity. When speed becomes an operational risk and which counterforces keep a system stable.
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