New ideas that are applicable and fun

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What my readers say about my articles

“Short, applicable and with some casual storytelling. What's not to like?”

“I loved the creative visual and the examples.”

“Short, sweet and value adding”

“I like how you keep it simple”

In my newsletter you will find:

  1. Practical tips on getting to problem-solution fit

  2. Methods on evolving from problem-solution fit to product-market fit

I research startups

I literally do science as a PhD-candidate. Focusing on problem-solution fit and product-market fit. I will share all the insights I discover along with my research.

Curly hair. Not a ginger.

Need personal 1-on-1 help?

I’ve mentored over 150+ startups in their early-stage. Some of the founders I’ve worked with:

What founders say about me

“It was an excellent, brilliant session. Thank you!” - Feedback from a founder I mentored

This doesn’t tell you much about what I do, so here are some more concrete examples


“Jeroen always motivated us to be ambitions while keeping us grounded, realistic and smart about what resources we had. He saved us a few times from doing unimportant, safe tasks and pushed us to get out there.” - Neva from Hii

“He bring optimism and realism at the same time. He asks "why" and then ask "why" again and again to unravel what a founder might have initially thought success was” - First-time founder Regina

Towards product-market fit

"He showed me the importance of clear selling message. Jeroen highlights the difference between problem-solution fit and product-market fit and provides a mental framework for testing distribution channels.” - Anonymous founder

“Sessions with Jeroen are well impactful. He helped me figure out how to communicate my product-market fit to investors, and in what order to display the information” - Martins from Dinesurf


I can help any startup that is pre-product-market fit.

Interested? Email me at to schedule a free intake.


Jeroen Coelen
PhD candidate on early-stage startups