Digital products, built as a system. And AI that pulls its weight.
I’m Dieter Möss. I have been self-employed since 2000 and, since 2012, have been developing digital products for BMW, Audi, Miele, Hamburg’s transit network HVV and the health insurer Techniker Krankenkasse, from the first user interview to the finished front end. Since 2025, I have also been designing and building systems with AI agents; the largest is in production at a Munich publisher.
From the question to the product.
Design Systems & Tokens
I develop new design systems, audit existing ones and prepare them for additional teams, including components, tokens, Storybook and the handoff to engineering.
More → When AI tools are supposed to build with your systemDesign Systems for AI
I describe components in machine-readable form, give tokens a documented purpose and set up automated checks in the pipeline.
More → When you need to understand what your users needUX Research & Concept
Interviews and usability tests provide the findings from which I develop user flows and prototypes as a basis for product decisions.
More → When the German Accessibility Act applies to youAccessibility to WCAG
I audit against WCAG, fix what is needed and anchor accessibility in the design system, drawing on experience from projects for HVV, TK and Audi.
More →Products in daily use.
Miele App
For a year and a half, I have been on the product team, overseeing the build-out and expansion of the design system, designing user flows for CookAssist and recipes, and using AI selectively to relieve the team.
1.5 years on the product teamAI Editorial System
Seven specialized AI agents handle research, drafting and fact-checking. Content is published only after the editorial team has approved it at three points. The system is in production at a Munich publisher.
7 agents · 3 approvalsSee the system →HVV Switch
I built the complete design system in Figma following Atomic Design, from the first wireframes to the components that went into production as designed.
1M+ downloads · 4.5 ★TK App
For an app with more than five million users, I designed design system components that meet the accessibility and data protection requirements of a regulated environment.
5M+ usersNeff in a Multi-Brand System
I developed a shared design system for Bosch, Siemens and Neff that lets each brand keep its own look, and migrated it from Sketch to Figma along with design tokens and a pattern library.
3 brands · 1 systemSee the case study →weed.de
For a medical cannabis platform in a regulated market, I was responsible for product development, UI design and team leadership, from strategy and the design system to user testing and branding.
2022–2024Vattenfall ENPURE
The goal was to make green electricity easy to understand, with a mobile-first approach. As UX architect and lead, I was responsible for the UX architecture and prototypes, with decisions based on usage data.
Product idea testedSee the case study → Automotive · WebAudi.de and Audi Motorsport
The corporate website and the motorsport presence serve many markets and were built to be multilingual and accessible to WCAG. As front-end track lead, I led five developers and was responsible for budget and resources.
Led 5 developersSee the case study →Four projects, a closer look.
Notes from real projects.
When the model is wrong: designing errors as a state
The notice “AI can make mistakes” offers no help when an error actually occurs. What the guidelines from Microsoft and Google provide for the error case and what follows from them for design.
Read more → Interaction designFive patterns for AI interfaces that already exist
Interfaces for generative AI can build on existing patterns. Five patterns that are already described in published design systems and well-known products.
Read more → Design SystemsPrototypes from your own system: what Atlassian reports
Atlassian has designers and product managers build prototypes in its own design system with AI and has openly described the problems along the way. What is transferable and what is not.
Read more → GovernanceWho checks the agents' code?
Which design system rules can be checked automatically, how an agent works with error messages, and what can be learned from automatic merging of dependencies.
Read more → Design TokensTokens instead of guessed color values
Hard-coded color values make a design system drift apart. How a three-tier token hierarchy and Tailwind v4 make guessing harder, with a verified example.
Read more → Design SystemsContracts instead of essays: describing components in a machine-readable way
Prose leaves a language model room for interpretation, which a component contract with fixed values, purpose, and prohibitions rules out. Plus the question of how an agent accesses this description selectively.
Read more → Design SystemsThree design systems that have opened up to agents
Teams at Indeed, Atlassian, and IBM have described publicly how they make their design system readable for AI agents. What they built and measured, and which conclusions cannot be drawn from it.
Read more → Design SystemsWhy coding agents fail at the design system
When coding agents fail at a design system, the cause often lies in knowledge that isn't written down in any document. What a design system needs to capture so an agent doesn't have to guess.
Read more → AI architectureNine building rules for an AI pipeline at a publisher
How does a publisher make sure an AI pipeline publishes nothing it cannot take responsibility for? Nine building rules from a system in day-to-day publishing, with a checklist for choosing a vendor.
Read more → Multi-agent systemsWhat building a multi-agent system requires
Seven specialized AI agents for a publisher's content production. Why the architecture was decisive, more so than the design of the prompts.
Read more →All articles
10 notes on AI systems, product thinking and design.
To the overview →Questions before we start.
Is a small first engagement possible?
Yes. A clearly defined task works well as a starting point, such as a design system audit or a prototype tested with realistic tasks. On that basis, you decide whether and in what form to continue.
Do you work with our team?
Yes. I work within existing teams alongside design, engineering and product management, most recently at Miele and previously at TK and HVV, among others.
Remote or on site?
I work remotely from the Munich area and am available on site by arrangement, for example for workshops.
Do you bill by time or at a fixed price?
Both are possible. I bill ongoing work on a time-and-materials basis and clearly defined packages, such as a design system audit, at a fixed price.
Will you sign a non-disclosure agreement?
Yes, even before our first in-depth conversation.
How soon can you start?
The start date is set by arrangement. Let me know when and to what extent you need support.
What if the project needs a whole team?
Then through methusalab, which I co-founded; a core team and specialists are available there for larger projects.
Why do we still need product designers and developers in the age of AI?