Reflections on building – The key to success is just doing
Ferrivia is building a smarter way to understand and manage iron deficiency. Their app helps women track their symptoms, labs, and supplements while providing clear, personalized insights. Their integrated service: combining lab testing with personalized support, is now available in Finland. Learn more at ferrivia.fi.
Mari Lahti and Erica de Wit, co-founders of Ferrivia
It all started with a problem
I’m a big advocate of the idea that the best startups are created to solve complex and painful problems. If there’s a lot of frustration around a specific issue, people are usually willing to pay for someone to come and solve it.
I know many founders who start their journey by looking for different problems to solve and then select the one with the best startup potential. I highly recommend this approach for anyone who wants to become a founder but doesn’t yet have an idea.
For us, it started with a problem that kept repeating around us. Besides working in tech, I’ve done sports nutrition coaching for over a decade. Late last year, I was giving an interview to Juoksija magazine about iron deficiency, vegetarian diets, and endurance sports. The reporter started sharing horror stories of women who had struggled with iron deficiency for years without a proper diagnosis. They were dismissed by the healthcare system and left to struggle, labeled as burned out or even depressed. Suddenly, I started hearing these stories from multiple other sources as well. I had, of course, coached athletes around this topic, but it took me by surprise that it wasn’t just athletes who struggled.
“At that point, I knew there was something here. I was able to tick several boxes on my “is this a good startup idea” checklist.”
I began to wonder how it is possible that something “as simple as” iron deficiency is addressed so badly. After some initial research, it became clear that iron deficiency, with all its dimensions, is actually quite a complex problem. What struck me the most was that one out of three women has low iron, and for some odd reason, low iron levels are treated as the status quo among women. It is what it is. Deal with it.
The validation process started with a simple survey that got 100+ replies in just a matter of days. At that point, I knew there was something here. I was able to tick several boxes on my “is this a good startup idea” checklist. The problem is complex, painful, and most importantly, extremely common.
The founding team
In my opinion, the earlier you find someone to build with, the more equal you both feel about the ownership of everything. I knew I didn’t want to go on this journey alone, so I started looking early. I was soon introduced to Erica through a friend from the ecosystem.
One of the most common reasons startups fail is conflicts between co-founders. It’s also quite uncommon to have a founding team that didn’t know each other beforehand. Erica is a second-time founder seeking her next project to join. She knew exactly what she wanted, and I was the ninth founder she trialed with. It also turned out that Erica had struggled with iron deficiency herself for a long time. Our initial coffee date turned into a full day of work. We hit it off straight away and decided to give it a try as a founding team.
While I’m more of a strategic thinker who tends to weigh different options, Erica is the powerhouse who pushes Ferrivia forward by just getting things done. It’s now been almost a year, and I haven’t had a single regret about our founding team. My advice for founders evaluating potential co-founders (and later early hires): if it’s not a ‘hell yes,’ it’s a ‘no.’
Proper validation takes time
We’ve both seen many startups developing solutions based on poor validation. You think you might have the best idea ever, only to release your product and find out no one is willing to pay a dime for it.
We followed the typical startup playbook by running dozens of discovery interviews with potential customers. The goal was simply to understand where the biggest pain points were when it came to iron deficiency and addressing them. If you’re not familiar with the concept of discovery interviews, I highly recommend The Mom Test.
Based on the interviews, we identified a couple of recurring pain points. The one we felt most capable of addressing was: “After I get my lab results, what does this actually mean and what should I do next?” The idea of a technical product to address this question was born, but we wanted to validate it a bit more before jumping into development, especially since neither of us has (or should I say, had) any technical skills.
Your MVP doesn’t have to be a technical product
All the interviews led us to our first MVPs. Since my background is in coaching, we tried to package and sell different coaching options around the problem. There were quite a few until the first one really took off. And it was as simple as sending people to take their iron labs and offering a 30-minute consultation on top of it. As this started selling, we validated what would later be turned into a technical solution while also gathering more insights from those consultations.
Nowadays anyone can build a technical MVP
As neither of us had a technical background, we had two options: either find a tech person to join our team or learn how to build ourselves. For us, outsourcing the development was never an option. As we weighed different paths, vibe coding tools were trending everywhere. So I started building in late April 2025. By the end of June, we were onboarding our first test users and building the product forward from there. At this point, in September 2025, we’re now onboarding our first paying users – a milestone that some startups never reach.
If anyone with an idea for an app says they can’t take it forward because they can’t code, they’re holding themselves back. It has never been this easy to prototype and build with zero technical skills. If working with actual code scares you, go forward with a no-code solution. At least start a conversation with ChatGPT describing what you want to build and asking what the best solution to build it with is. Honestly, that’s what we did.
It’s all about speed
The most valuable resource for a startup is time. And time is always running out. We’re extremely grateful for the Startup Foundation grant that allowed us to jump full-time while still in the validation phase. For many founders, this is the phase they are in while still having other work commitments. For us, the choice was easy: let’s give this thing a go and our full focus for three months. If it doesn’t seem to fly, we can always go back to working on something else. In September 2025, we’re still here with a product that is making revenue.
So, for anyone wondering if they should give their idea a try, I encourage you to think: what’s the worst that could happen?
– Mari Lahti
