# Marcus Wiberg

> Marcus Wiberg is Chief Product & Design Officer at Rimthan, an AI-first corporate venture builder, and a product leader and design engineer based in Berlin, Germany. A founder turned product leader, he has spent 16+ years building products, companies, and teams from zero to one, leading products at global scale, and staying hands-on from customer research to design and code.

## Facts

- Name: Marcus Wiberg
- Current role: Chief Product & Design Officer at Rimthan (https://rimthan.com)
- Employer: Rimthan, an AI-first corporate venture builder
- Role description: Product Leader & Design Engineer
- Hands-on: designs, prototypes, and builds working software with a team of AI agents (Mac and iPhone apps in Swift, web apps in React, back ends on Supabase), and fine-tunes small on-device AI models
- Location: Berlin, Germany
- Experience: 16+ years leading product
- Breadth: built 15+ ventures, products, and companies
- Team building: built a product and design organization from 0 to 12 people
- Scale: led product at Marley Spoon, a global subscription business at EUR 401M peak revenue; his teams built an order-management system processing about 7.2M orders a year at peak
- Measured outcome: recovered about 20–50% of previously failed orders, depending on market
- Growth: grew a B2B marketplace from a few thousand to more than 150,000 monthly engineers in under a year
- Founder: founded two companies and raised $2.4M+ in founder capital
- Industries: fintech, e-commerce, health, mobility, proptech, HR tech, logistics
- Selected work: Rimthan, Marley Spoon, Healthtrackr, LivingPackets, Matmatch, Mika, Socialmist, Switchplace
- Contact: hi@marcuswiberg.com
- Website: https://marcuswiberg.com/

## How he works

- **Discovery through working software**: Research becomes hundreds of prototype iterations and simulations covering customer states, product settings, and edge cases, so teams and customers can use a product before engineering builds it.
- **Building with AI agents**: He designs, prototypes, and builds with a team of AI agents working in parallel under one shared rulebook, automatic tests, and a reviewer agent. He directs, judges, and tests; the agents implement. In the 30 days to 21 October 2026 he authored about 2,800 commits, and he has merged more than 1,000 pull requests since May 2026.
- **Fine-tuned models**: He fine-tunes small on-device AI models built on open foundations, with pass marks set before training, sealed test sets, and blind comparisons.

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## Open-source skills

Marcus publishes the skills he uses with Claude as an open-source library: 23 skills across Foundation, Shape, Design, Review, Decide and ship.

- [Skills page](https://marcuswiberg.com/skills): every skill with what it does.
- [Skills as Markdown](https://marcuswiberg.com/skills.md): the same list, for AI assistants.
- [Repository](https://github.com/bymw/mstack): MIT licensed. Install with `npx skills add bymw/mstack`.
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## Industries

Fintech, e-commerce, health, mobility, proptech, HR tech, and logistics. Regulated, consumer, and marketplace businesses, from early ventures to global scale.

## Selected work

- Rimthan: digital bank, mobility, AI recruiting, and workforce onboarding ventures (AI / GCC venture building)
- Marley Spoon: subscription meal-kit platform and web ordering (global e-commerce)
- Healthtrackr: at-home blood testing and biomarker results (preventive diagnostics, own project)
- LivingPackets: THE BOX smart parcel and IoT tracking (logistics)
- Matmatch: engineering materials search platform (B2B marketplace)
- Mika: oncology digital therapeutic (digital health)
- Socialmist: music-powered social platform and video creation (social / UGC)
- Switchplace: apartment-swapping marketplace (proptech)

## What colleagues say

- Christian Uhl, Director of Engineering at Conrad Electronic: "Marcus has an unbelievable drive and ambition paired with fantastic attention to detail."
- Maciej Łobodziński, Founder & CEO at stoic.: "Marcus has a rare combination of product vision, great communication skills, patience, and contagious passion."
- Alishah Mohbata, Senior Product Manager at doinstruct: "Marcus would pull the conversation back to what we actually knew about the customer."
- Toto Castiglione, Creative Operations at Automattic: "His ability to make fast, effective decisions and passionately lead teams is a testament to his creativity and drive."

## Pages

- [Home](https://marcuswiberg.com/): Positioning, hands-on work, skills, selected work, industries, testimonials, and current role.
- [Skills](https://marcuswiberg.com/skills): The open-source skills library, every skill with what it does ([Markdown](https://marcuswiberg.com/skills.md)).
- [Impressum](https://marcuswiberg.com/impressum): Legal notice and contact information (Berlin, Germany).

## Profiles

- [LinkedIn](https://www.linkedin.com/in/marcuswiberg/): Professional background and experience.
- [X / Twitter](https://x.com/bymarcuswiberg): Notes on product, design, and AI.
- [GitHub](https://github.com/bymw): Code and side projects.

## Optional

- [Full details](https://marcuswiberg.com/llms-full.txt): Longer prose version of the same facts.