Hello, I’m Mariesa 👋🏽
I help early-stage teams find product-market fit by building it, not just advising on it. Discovery to validated, working product, as one person, in weeks.
Most 0-to-1 work needs a researcher, a designer, and an engineer. I’m all three. I run the discovery, design the experience, and ship the actual prototype, so you get real signal from real users fast, without assembling a team to get there.
Product-Market Fit Sprint
A fixed-scope engagement: from ambiguous problem to a validated prototype in front of real users. Discovery, design, build, test. You leave with signal, not a deck.
AI Solution Building
For teams with AI ambition and little shipped: identify the high-leverage use case, build the working solution, embed it in the product or workflow. A thing that runs, not slideware.
Fractional 0-to-1 Partner
Ongoing hands-on partnership for founders who need a builder-operator through an extended ambiguous stretch, not a one-off project.
How I work
No long ramp-ups. No big teams to coordinate. Just a hard problem, and a working answer in front of real users faster than you’d expect.
Because I run the whole 0-to-1 loop myself, discovery, design, and build, there’s no handoff lag and no telephone game between a researcher, a designer, and an engineer. You get one person who can sit with your users on Monday and have something real in their hands by the end of the sprint.
Three steps from ambiguous problem to real user signal and something that runs.
1. We find the real question.
Most early-stage problems are fuzzy on purpose, that’s what makes them hard. We start by getting specific: who is this for, what are they actually trying to do, and what would we need to see to know we’re right. You leave this step with a sharp question worth answering, not a vague mandate.
2. I build and test, in weeks.
I design the experience and ship a working prototype, real enough to put in front of real users, not a clickable mockup or a slide. Then we get it into their hands and watch what actually happens. This is where assumptions meet evidence, and where most teams are surprised by what they learn.
3. You leave with signal, and something that runs.
At the end, you have two things: a clear read on whether this is worth pursuing, and a working artifact you can build on, demo to investors, or take straight into your roadmap. No dependency on me to make sense of it. The point is momentum, not a retainer.
Have a hard problem you want built and validated, not just advised on?
Are you an Ideālist?
The best early-stage teams don’t wait for certainty. They build the smallest real thing that tells them the truth, put it in front of users, and let evidence set the direction.
That’s how I work, and who I work best with: founders who would rather have a working prototype and real signal in a few weeks than a polished strategy deck and another quarter of debate. If you have a hard, ambiguous problem and you want it built and validated, not just analyzed, we’ll get along.
Subscribe to my newsletter ‘Wild Enough’ on Substack.
I write regularly on product, creativity, and the practice of paying attention. Wild Enough is where I give myself (and you) permission to be a little unruly in a world of systems and metrics.
Idealis 