The voluntary carbon market is broken. Callirius is here to fix it. The world is lacking high-quality, nature-based solutions to actively decarbonise the atmosphere. We’re building the platform to finance high qualitative climate solutions through a data-driven, science-backed, and well-regulated framework.

Explore our solutions

We favour nature-based solutions at Callirius. This is because they are the only scalable and economically viable solution for the active removal of CO2. Every climate project you find through our platform is qualified to the same standards. 

All of our solutions are…

High Quality

We manage a dynamic and diverse climate portfolio with nature-based climate solutions around the globe. All climate solutions are screened to ensure quality, passing strict evaluation criteria. This way we can maximise your climate impact.


We ensure full transparency on all of our solutions. Tracking your carbon credits on-chain means every transaction is transparent and easy to access, eliminating hidden pricing and unnecessary red tape. You get the relevant carbon certificates at the right price.


Our climate projects create true community impact by focusing on solutions that strengthen the local biosphere. We work exclusively with projects which guarantee a net positive impact on the environment, biodiversity, social justice, and human rights.

Meet the team​

The Callirius team uniquely brings together over 100 years of experience in the finance and banking sector. This enables us to create tailor-made financing solutions through a data-driven, science-backed, and well-regulated framework.

Ebrahim Attarzadeh

Co-founder, CEO & Chairman

After more than 20 years in Investment Banking in various leading positions, latest as CEO of Stifel Europe Bank/Mainfirst Bank, I decided to actively contribute to solving our biggest challenge: climate change. Outside work you find me doing watersports, skiing and sharing time with my three boys.

Rudolf Maier

Co-founder, Head of Distribution

I have been an investment banker for more than 25 years, and now it was time for a change. I couldn't be more excited to start a new episode in the space of green and sustainable assets with my friends and former colleagues. I love to see my 2 boys growing and hope they have the opportunity to enjoy our wonderful planet as much as I do.

Michael Grohmann

Co-founder, Head of Project & Policy

If you can combine the skills learned from 20 years in banking and the passion for nature to fight climate change, it is not only a privilege but also a duty. I want to contribute to shaping a sustainable and liveable future for our kids.

Tim Schuldt

Co-founder, Head of Product & Technology

I am an ex-Banker with a passion for programming and decentralised ledger technology, helping the world in its fight against climate change by combining my technological and financial know-how.

Dr. Ulrich Franke

Financing Solutions & Advisory

Asset-Backed Financing has always been my professional focus. Therefore, I am supporting Callirius and the community to find ways to combine the concept of secured financing with an understanding of nature as an asset in order to create Nature-Backed Financings.

Thomas Götschmann

ad-interim CFO/COO

I am a serial entrepreneur, convinced we can save our planet with the right incentives to auto-control carbon emissions and invest into carbon removal.

David Steinmetz

Climate Solutions Specialist

I am an environmental scientist with a background in economic geography. I want to contribute to a sustainable future by helping to implement impactful climate solutions. In my spare time I can be found hiking in the mountains or playing roundnet.

Julian Böll

Data Scientist

I am an applied scientist with a background in experimental and applied fundamental physics and chemistry. The Climate Crisis drives me to contribute my knowledge of natural sciences and passion for r&d to the global effort of carbon removal. Outside of work and science I am typically in the mountains: mountaineering, rock climbing, riding my mtb or splitboarding.

Marina Herías-Sáenz

Business Strategist

I am a management engineer, with experience as a business strategist and consultant in the Financial industry. I am determined to bring Climate Finance into effective urgent action to add constructive value to global society. Outside the office you can likely find me in the mountains, enjoying live music, between the cookers or on my yoga mat.

Jonas Landgraf

Product specialist

After working in banking and e-commerce, I realised we are heading towards a cliff and it is time to build a bridge towards a sustainable future, both for us and the next generations. I am proud to be part of the fight against climate change. In my spare time, you can find me playing beach volleyball, skiing and spending time in the beautiful little forest next to my home.

Callirius means “king of the wood” in Roman Britain. Taking care of woodlands plays a key role in reducing our carbon footprint, meeting the 1.5°C targets, and fighting climate change.

Meet our advisory board​

With expertise combining science, project know-how, and market insights, our advisory board brings together an abundance of knowledge around the lifecycle of carbon credits.

I am Professor of Corporate Management at the University of Trier. I am a research and teaching expert in innovation and sustainability management of SME companies, in particular in the decarbonization of industrial SMEs.

I am Venture Partner at AENU, an impact-tech VC, and Sustainability Advisor at UnternehmerTUM, and Board Member of the Circular Economy Initiative of BDI. Since 2007, I have worked on sustainability and impact issues at various corporates and in the startup scene.

I have worked as head of marketing at MyClimate, a Swiss-based NGO focusing on climate protection and sustainability measures. I am an expert in communications and sustainability. I am also a football aficionado and a passionate hiker.

I am a founding partner of Lucy Capital, an early stage VC investing in ClimateTech, Health and People Empowerment. Before I founded thriving ventures in travel and fashion. I also worked in the successful development of Zalando and some of its portfolio companies and as a PE restructuring manager.

I worked in climate tech for ten years, focusing on energy and mobility as a corporate manager, founder and VC. Now I explore the intersection of climate and crypto. I spend my off-screen time with my family, travelling and optimising my life for longevity.

Come and join our team

If you have expertise in climate finance, climate science or carbon markets or are a professional climate enthusiast, we welcome applications on a continuing basis.

Contact us