Your sparring partner on speed dial

Spend time on the right things — weekly check-ins and unlimited DMs keep you on track to product-market fit.

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Additional brain

"Jeroen is an additional brain. Someone who shares your ambitions, has relevant experience and knowledge, and can provide support at a deeply personal level"

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Julia

Founder of Badge

Now doing sales calls confidently

"I needed a structured approach to scale my sales calls and tactics for smoother conversations. With Jeroen’s input, I walked into those meetings feeling more confident than ever."

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Philipp

Founder of Rollouter

Actionable advice with relevant examples

10/10 would recommend. Jeroen helped me get better focus on what's the most important priority. Asks the right questions to dive deep and gives very actionable advice with real examples based on the many startups he worked with.

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Jayson

Designer at Marvel

Sanity checks and action points

Jeroen is the best! Helpful insights and sanity checks. Walked away with action points we are excited to execute on. Would recommend for any founder.

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Eric

Founder of Ailixr

Mindset shift to the customer

"He helped me to shift my mind away from what I offer to focus on the customer. From supply to demand. This has helped me to sharpen my value proposition immensely"

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Dylan

Founder of Bildung Academy

Hard and honest feedback

"Jeroen doesn't beat around the bush. He highlighted what customer information I missed in a direct way, I immediately knew where to focus. That's the kind of feedback I prefer to hear, cold and early."

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Javier

Founder of Nummary

Learn to think like a startup

"By working with Jeroen, I've learned how to turn big ideas into small experiments. This increased momentum and focus for our startup. We now know what works, without spending 6 months of building it."

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Caroline

Founder of Grape Genius

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Over 350 startups

Have received my advice

1000+ founders

Felt my energy

25+

Accelerator cohorts got my workshops

My way of working

Mentoring Subscription - Jeroen as a Service (JAAS 👸)

  • 2 hours call time per month

    Free to divide: 4×30 min, 2×1 hr, etc.

    4 hours per month possible

  • Weekly fixed timeslot as a basis

    But very flexible to reschedule

  • Unlimited DMs

    You can email me or WhatsApp me unlimited questions throughout the week

  • 1 hour kick-off deep dive

    The first call we take a little longer to get all the cards on the table

  • Cancel each month

    14 day free refund, no small print

    What we cover in calls

    Some examples of what I cover

    Sanity check on your priorities

    Should you focus on your MVP, outreach or your marketing campaigns? Is funding the right moment for you?

    Find the right market to grow in

    Based on your calls and feedback from customers, I help to identify the best market to grow

    Building the right MVP

    Which features to include, and which not? I'll act as a sounding board to make sure you are not over-engineering your v1.

    Outreach messaging optimisation

    How to write a message that converts? I will inspire with ways of moving the conversation forward.

    Landing page feedback

    Based on our work, I help to optimise copy on landig pages.

    Validate the right things

    Offer examples of experiments to run as inspiration suited to your situation

    Improve your listening skills

    What is a good interview script? Which questions to ask? How to structure the conversation to land insights and sales

    Pep talk when you are down

    Building a startup is a rollercoaster. I will share anecdotes and tips how other founders beat the slump.

    Intros to my network

    If I see an opportunity for you to learn from somebody in my network, I'll intro you.

    Our Team

    Have you ever seen them in the same room together? 😏

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    Jeroen the Mentor

    Guiding light

    Jack of all trades: Trained as a designer, ex-founder, ex-product-owner, innovator at corporates and now experienced mentor.

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    Jeroen the Scientist

    Researcher of product-market fit

    My PhD focuses on how early-stage founders design their startup. Fringe insights from academia.

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    Jeroen the Energizer

    Battler of downs

    Doing a startup is a rollercoaster. I've coach founders through hard times, focusing on the upside of things.

    From B2C to deep tech

    Experience with many startup types

  • Consumer hardware & software

    Trained as a product designer, I love tailoring solutions and propositions to consumers. Marketing to consumers is different than businesses. I'll teach you how.

  • B2B

    How to sell to businessess? How to segment a market if there are 4 stakeholders? Having advised many B2B startups, I help you to navigate that maze.

  • B2G (Government)

    Governments are a peculiar customer type. Mandate is scattered, the organisations can seem like an impenetrable fortress. I will help you get there.

  • Deep Tech

    Science based startups or academic founders to find their beachhead market.

  • Pricing for mentoring

    Jeroen as a Service (JAAS 👸)

    Pricing based on startup maturity

    Pony

    Yearly revenue below €25k

    €190

    / month (excl. VAT)

    Schedule free get to know call

    €250

    / month (excl. VAT)

    Schedule free intro call
    • ARR below €25k

    • or

    • For bootstrapping startups

    Horsey

    Yearly revenue between €25k and €100k

    €250

    / month (excl. VAT)

    Schedule free get to know call

    €300

    / month (excl. VAT)

    • ARR between €25k and €100k

    • or

    • Recent investment of €50k+

    Unicorn

    Yearly revenue €100k+ or VC-Backed

    €370

    / month (excl. VAT)

    Schedule free get to know call

    €490

    / month (excl. VAT)

    • ARR above €100k

    • or

    • Recent investment of €250k+

    Quick get to know chat?

    Leave your email and I'll reach out

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