Your sparring partner on speeddial

Sanity checks, critical feedback, and pep-talks for startup founders—All within minutes.

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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

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 but 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

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10 years

Experience as mentor

352

Early-stage startups worked with

25+

Accelerators worked at

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.

My way of working

Mentoring Subscription - Jeroen as a Service (JAAS 👸)

  • Unlimited DMs

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

  • 60 minutes call time per week

    Quick call, short calls, sometimes you just need a sounding board. Schedule quickly, I'm flexible, only a few days ahead sometimes.

  • Frameworks to organise your thoughts

    I give you small exercises to prepare for our calls to hit the ground running

  • Cancel each month

    14 day free refund

    First month €100

    Almost any startup type

  • 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

    Based on startup funding type

    Jeroen as a Service (JAAS 👸)

    Monthly subscription

    €250

    / month

    Schedule free first session

    €500

    / month

    • Unlimited questions over chat

    • 60 minute calltime per week

    • 14 day free refund, no questions asked

    • First month €100, stops automatically

    Schedule a free mentoring call

    20 minutes, no strings attached

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