I wasn’t looking to build a SaaS. But one remark, almost an offhand comment, changed everything. Here’s how that idea became Marty.

Like many people, I thought founders started from a brilliant idea and built a company from there. That all you needed was that famous idea (which I’d been trying to find for years) and then execute on it.

A kind of modern-day Eureka moment.

Looking back, I’ve come to see that in our case we started from a very vague concept, refined through iteration, to solve a real problem for our users.

Obvious to a seasoned entrepreneur. A necessary path for anyone building their first business.

Here’s how our idea evolved, and more importantly, what I learned from it to help you avoid the same pitfalls.

The opportunity that changes everything

The starting point didn’t even come from me. The tradespeople angle came from friends close to that world.

Two phrases stuck with me:

  • “It would be great to see tradespeople on a map, like apartments on Seloger”
  • “There’s no Doctolib equivalent for tradespeople, there’s a gap to fill”

At the time, these ideas didn’t interest me: too broad, too far from my skillset. We’d later understand that imagining a tradesperson spending their days behind an online calendar wasn’t realistic.

In that sector, delays are counted in days, not minutes.

The trigger: Late 2024, with the explosion of LLMs, I imagined a solution that simplifies life on both sides: a system capable of handling appointment scheduling automatically by SMS, without forcing the tradesperson to change their habits.

At that moment, the technical challenge grabbed me and I thought: there’s a real opportunity here.

Validating an idea (better than we did)

With my co-founder at the time, we decided to dig in seriously.

What we did right:

  • 15 interviews with tradespeople (carpenter, renovation company director, plumbers)
  • Open questions about their frustrations
  • Analysis of the tools they use

These exchanges gave us concrete information, impossible to find in a PDF report.

Recurring problems:

  • Heavy administrative burden
  • No time to manage visibility (website, social media)
  • Dependence on expensive, low-quality lead generation platforms

We complemented this with macro research, competitive analysis, and client-side interviews.

We wanted to solve everything (visibility, admin, client relationships) with a single product.

Attractive on paper, but in reality impossible to bootstrap with two people.

Lesson: Wanting to build “the perfect product” is an illusion. Better to do one thing very well.

My first strategic choices

Faced with that ambition, I took time to design a product addressing all those needs and broke it down into functional building blocks I could develop in order.

My priorities at the time:

  • Clean code above all: avoid significant technical debt from the start
  • Speed to market: 3 months for the MVP to reach the market as quickly as possible
  • Broad scope: visibility, admin, and client relationships

Quickly, I understood I needed to change strategy: focus solely on tradesperson visibility and push everything else back.

A decision that clarified our message and accelerated our development.

Advice: If your idea is too broad, reduce the scope. You’ll gain clarity and increase your chances of success. Always validate with potential users.

From freelance to founder: the leap

This phase came at a good time: I’d finished my freelance contract and could dedicate 100% to Marty. But I quickly discovered an important difference:

  • As a freelance Data/AI engineer: I was selling a skill to someone who knew its value and had a clear ROI in mind.
  • As a founder: You have to convince without proof. And selling a product is much harder.

On the technical side, it meant managing everything:

  • UI/UX (twice for mobile)
  • Complete backend
  • Infrastructure from scratch

Personal win: There was nobody behind me. If I didn’t do it, it wouldn’t get done. I had to cover every layer: product, front, back, deployment, data.

In 3 months, I’d built a complete product. Not because I was full-stack to start with, but because I had no choice. And honestly? That steep learning curve was one of the biggest gains from this adventure.

Your environment: a lever and a challenge

One thing I didn’t expect: the impact of the people around you. When you launch a project, the people close to you react. And not always as you’d expect.

Two common attitudes:

  • Worried support: “That’s brave… but are you sure?” Caring, but full of doubt.
  • Incomprehension: “Why leave a stable situation?” Until it works, some see it as a hobby.

What I learned: The people around you want to help, but they project their fears. Don’t try to convince everyone. Surround yourself with people who understand the entrepreneurial path (communities, founders). Their energy will carry you.

And if tomorrow you meet an entrepreneur, be kind to them. It can change their trajectory.

What I took from this first phase

Strengths:

  • Moving from idea to action
  • Accepting pivots
  • Leveling up (full-stack, product mindset)

What I’d do differently:

  • Reduce the scope from the start
  • Revalidate each pivot with real users
  • Better anticipate the freelance-to-founder transition

My advice if you’re starting out:

  • Focus on one major problem
  • Test each hypothesis with real people
  • Prepare the mental transition (income, social circle)
  • Keep a financial buffer to learn without pressure
  • Set a time frame and clear objectives

Yes, it’s a massive challenge. But what I gained is worth the sleepless nights: learning to ship fast, to convince, to build. Basically, going from executor to creator. And no freelance contract would have taught me that.

Have a business idea? Don’t procrastinate.

Here are 3 steps to start validating it this week:

Talk to 3 people in the space. Not to present your idea, but to listen to their frustrations.

Write down your observations.

  • What problems?
  • For whom?
  • Why now?
  • Would they pay for a solution?

Set a testable goal for the next 2 weeks. Example: 10 interviews, a quick landing page, pre-registrations.

One of a startup’s biggest assets is speed.

Move fast, iterate, understand your audience, and don’t build anything before you’ve validated that the need is real and people are willing to pay.

If you want to get up to speed quickly, watch the best minds on the Y Combinator YouTube channel. It’s a goldmine for understanding what to do (and avoid) from day one.

What’s next in this series

In the next articles, I’ll cover:

  • “From vague idea to real product” - My experience building the product from scratch.
  • “Solo technical founder: choosing your stack and laying solid foundations” - Frontend framework, architecture choices, AI provider, and more.

If these topics interest you, contact me by email or follow me on LinkedIn.

The goal of this series? Sharing concrete lessons to help other builders avoid the same mistakes. Every article will be actionable.