Chief of Staff & Catalyst
#justcallmetoby
My full name is Tobias Marcus Zielke - but in the SaaS world, most people know me as Toby.
Together with my wife and our cats, I’ve been living for many years in the region near Cologne.
This site is here to give you a better first impression of why I might be the right catalyst and Chief of Staff for your organization.
That’s me: straightforward, clear, direct – but with a touch of unconventional thinking and a sense of humor…
…just like my logo.
Current CV
(Version July 2025 ~8.2 MB)
That adds up to quite a range of responsibilities.
With nearly 25 years of experience in successfully building, scaling, and restructuring international companies across eCommerce, IT, marketing, sales, and technology, I combine operational excellence with entrepreneurial vision.
As a fast thinker, strategic catalyst, and pragmatic doer, I bring energy, structure, and enthusiasm into dynamic business phases - from developing sustainable business models and leading or realigning C-level and mid-level teams to building scalable processes, KPI-driven management structures, and high-impact programs for customer loyalty and talent development.
My passion as Chief of Staff lies in actively shaping strong and resilient company cultures – with a focus on diversity, authentic leadership, working project structures, and the development of high-performing, motivated teams.
As an experienced executive in strategic business development, I support organizations through growth and transformation phases.
With a clear focus on efficiency, impact, and long-term market positioning.
National and international leadership experience, personal budget responsibility in the double- and triple-digit million range, and extensive experience in communication with authorities and investors complete my profile.
What defines me: vision, clarity, and momentum
I'm not a classic consultant who delivers slides – I share the risk.
I dive deep into structures, identify blockages, and help teams get moving again.
In doing so, I combine systemic thinking, strategic clarity, and an unflinching eye for what truly makes a difference.
In my projects, there's rarely one single big lever – but always a dozen small adjustments that, together, shift speed, direction, and culture.
That’s my playing field:
I connect people, processes, and perspectives – to make progress not just possible, but likely.
And sometimes, I'm just the catalyst.
Why I’m the one people call in critical moments
That’s when I get the call:
When growth is happening too fast, structures start to crack, or the gap between strategy and execution gets too wide.
Or when a company has big plans – but no one to provide the operational backbone.
Here’s what I ask:
- Who's holding things back – or what is?
- Where is clarity missing when it comes to direction and accountability?
- What recurring patterns do we see – and what’s driving them?
- Which meeting no longer serves a purpose – and which one are we missing?
And then we get started. Structured. Clear. Calm. But relentless.
My approach: direct – principled – collaborative
I’m not the loudest voice in the room. I don’t bring buzzwords. I bring integrity.
I listen, I ask a lot of questions, I think fast - and I act with deliberation.
Those who work with me know: I say what needs to be said - even when it’s uncomfortable.
First: always with respect.
Second: never without a solution.
Never without context.
And never without the willingness to take responsibility.
At the same time, I’m known for creating space with lightness and humor - so that change isn’t seen as a burden, but as a chance.
That’s why many CEOs see me not only as a catalyst for change -
but as a strategic sparring partner and catalyst for leadership.
Professional highlights
~25 years in senior leadership roles in startups, scale-ups, and corporations
Managing Director, Chief Executive Officer, Chief of Staff, Chief Operating Officer, Chief Sales Officer…
Solid experience in growth, restructuring, leadership enablement, and M&A preparation
Hyperscale business, recruiting, coaching and training of executives, exit preparations, and due diligence projects...
Collaboration with C-level executives, investors, supervisory boards, and regulatory authorities
KPI/OKR development, management reporting, investor relations, and employee transfer companies...
International leadership experience (DACH, Europe, North America)
Managed up to 18 country operations, extending beyond national borders...
Operational budget responsibility up to the triple-digit million range
Hyperscale with growth rates of 200-300% annually, EBT margins above 50%
Industry experience: IT, Tech, eCommerce, SaaS, Media
Ad server technologies, mail server technologies, b2c eCommerce, agency/publisher
My motivation:
Purpose, impact, and people
What drives me is not an exit, but the impact on business and people. I believe in organizations that aim to create change - in integrity in leadership, transformative culture, and sustainable thinking.
I am a builder, mentor, motivator, and catalyst,
firmly believing that true transformation begins with enthusiasm!
In my career, I’ve seen many business models and even more visions. But in the end, it always comes down to the same thing: people who want to take responsibility, but need someone to bring structure, clarity, and execution.
Cave Diving
In my free time, I enjoy diving. My favorite places are flooded mines or natural caves. As a technical diver on a closed-circuit rebreather, exploring new areas is my passion, planning is in my DNA, and focus is essential. Yet, I find peace during these challenging dives.
Cave diving teaches me a lot: about risk, decisiveness, and trust. About the ability to move safely in complex systems. These are qualities that make all the difference in the business world as well.
I am also a catalyst for ambitious divers and regularly help "overhead" beginners explore new areas or further enhance their skills.
I hope this has piqued your curiosity for a conversation.
You can find my contact details on my contact page, or visit me on LinkedIn.