Sparring Instead of Coaching: How Julia Derndinger Has Been Guiding Founders for 10 Years
"Happy Bootstrapping" Volume #59
Julia Derndinger is based in Berlin and has been working as a sparring partner for entrepreneurs for ten years – after more than 20 years as a multi-time founder herself. She runs two models in parallel: In her 1:1 retainer for €5,000 a month, she works with up to five later-stage founders with revenues between €5 and €70 million.
Alongside that, she runs TeamJulia, her founder program at €1,000 a month with up to 20 participants per cohort. In the conversation with Andreas, the topics are the CEO role, why she doesn’t offer frameworks and is still fully booked, and why most startups don’t fail because of wrong decisions but because of decisions that were never made.
This is a summary of Episode 171 of the “Happy Bootstrapping” Podcast (German).
Two Models for Two Very Different Audiences
Julia’s business consists of two clearly separated brands. Derndinger GmbH is the 1:1 sparring for later-stage entrepreneurs. Five retainer clients in parallel is her full capacity. Average client tenure sits at three years and longer. One of her better-known references is Christoph Behn of die Kartenmacherei, whom Julia accompanied from €10 to €70 million in revenue.
TeamJulia is the other model – a twelve-month founder program at €1,000 a month, running remotely, with one in-person strategy day per year in Berlin. Up to 20 participants per cohort, 80 percent of them bootstrapped, with a 50 percent share of women. The program is led by Johanna Küster, supported by external experts such as Christian Angel and Felix Schlegel, who are active entrepreneurs with multi-million revenues themselves.
Sparring Is Not Coaching
When the word “coach” comes up, Julia visibly pulls a face. Coaches work with frameworks, with questions, with curricula, she says. Her clients have no patience for that. What she delivers instead, she describes very plainly:
“I genuinely enjoy serving my clients. I’ll happily make them a coffee.”
In practice, that means: every week, the biggest problem on the table gets solved. No workshops, no tool licenses, no method. Availability is same day, no contract, cancellable monthly. What sounds risky is Julia’s deliberate lever: she has to prove every month again that she’s worth it. And her clients still stay – on average three years and longer.
The CEO Role as a Playing Field
One of the recurring topics in Julia’s sparring is the question of who in a founding team is actually the CEO. She uses an image for this that sticks:
“The job of the CEO is to define the playing field. What sport are we playing? Are there six on the field or eleven? Do we need a coach, do we need a chef?”
By Julia’s definition, the CEO is the club owner. Not the player who goes into goal when the goalkeeper falls ill. His or her only role is to make sure the company survives. Most startups, Julia says, don’t clearly work out in the first three to five years who actually holds that role. As a result, everyone has it or no one does – and that’s exactly what makes teams dysfunctional.
Bottlenecks and the Question of Missing Decisions
In the later-stage companies Julia works with on retainer, the bottleneck is rarely the customer. Product-market fit is usually already there. What’s left are time and money as resources – and with that, the question: What do I focus on this week?
Julia likes to ask her clients what they would do if money weren’t a bottleneck. The answer sharpens what really matters. In her experience, most companies don’t fail because of wrong decisions but because no decision gets made at all:
“Most startups don’t go under because of the wrong decision but because they don’t make any decision at all.”
TeamJulia as Insurance – Even for Investors
Julia has a thesis about her founder program that lands hard in the conversation: TeamJulia is essentially insurance. Over twelve months, she notices when a co-founder conflict is brewing, when product-market fit isn’t there, when the sales pitch is too weak. And she notices faster and more honestly than investors, because the environment is more vulnerable and participants are not dependent on her. Her conclusion: anyone investing €100,000 in a startup should put €12,000 of it into TeamJulia. Of the seven VC-funded teams Julia has had in the program so far, all of them closed a successful round afterwards.
Gut Feeling as Compressed Experience
Julia describes herself as a doer – fact-driven, fast, always pulling numbers, data, facts. And she still decides by gut feeling. Her reframing of this is one of the most memorable moments in the conversation:
“Our gut feeling is the sum of all the decisions we have ever made. Our body can process that faster and better than our brain.”
Because entrepreneurs have to carry their decisions through themselves, she argues, you need that softer factor. Otherwise the commitment doesn’t hold. The ability to reflect, for Julia, is therefore entrepreneurial skill number one.
The full episode is now also on YouTube (German only):
Key Takeaways
Sparring instead of coaching: No frameworks, no curriculum – every week the biggest problem at hand gets solved.
Two clearly separated models: Derndinger GmbH for later-stage retainers, TeamJulia for ambitious founders from around €250,000 in annual revenue.
The CEO role has to be named: Who is club owner and who is player decides whether a founding team works or doesn’t.
Learnings for Founders
No contracts can be a feature: Monthly cancellability forces you to deliver – and still creates relationships that last several years.
The bottleneck is rarely the customer: In later-stage companies, the lever is time, money and focus, not acquisition.
Missing decisions cost more than wrong ones: Most companies fail because of unclarity, not because of mistakes.
People skills are learnable: But only if you recognize that they matter – without them, you stay self-employed and stuck.
Gut feeling isn’t esoteric: It’s the compressed experience of every decision you have made so far.
Happy Bootstrapping is a German podcast where I interview bootstrapped founders, indie hackers, and solopreneurs about their startup journeys.
Over the years, I’ve connected with many successful entrepreneurs who have built e-commerce shops, SaaS platforms, mobile apps, content businesses, or hybrid models.
Furthermore I am a bootstrapper myself and growing my DevOps-as-a-Sercice and Web Operations Company “We Manage”.