Flatmate.dk: fit without a fake percentage

A naming brief became a product question

Two friends asked me to help name a matching service for people looking for a flatmate in Copenhagen. The market was Tinder-shaped: swipe a face, message a stranger, hope the fridge survives. They wanted the first conversation to carry more useful information.

The product question emerged from the naming work. A shared home depends on repeated scenes: Tuesday dinner, Sunday cleaning, a guest arriving late, one bathroom before work. A profile built around appearance or broad personality labels leaves those scenes unnamed.

One ordinary Tuesday

Flatmate organises compatibility around rhythm. When do you cook? What counts as quiet? How long can dishes remain in the sink? How much notice should a guest give? These are small questions until two people disagree inside the same kitchen.

The product does not promise to predict a household. Its job is to surface the conversation before a lease makes that conversation expensive.

Flatmate.dk

Shared-home decision dossier

Illustrative dossier · live product

Fit is explained in words.

Concrete reasons, disagreements and unknowns replace a compatibility score.

Reason to continue

Both prefer quiet weeknights and shared dinners twice a week.

Disagreement to discuss

One hosts friends weekly; the other wants advance notice.

Unknown before viewing

Cleaning standards have not been answered by both people yet.

One decision dossier carries the experience

The live product now spans Discover, Rooms, Matches, Messages and Profile. It supports seekers, hosts, people doing both, and household members. Across those surfaces, fit is explained as concrete reasons, possible disagreements and unanswered questions.

For example, a kitchen mismatch can be written as “you cook most weeknights; they rarely do” instead of disappearing inside a percentage. The sentence gives two people somewhere to begin without claiming that one answer predicts a successful household.

Interface choices

Scores stay out of the conversation

Stars and percentages imply more certainty than the product has earned. Scenarios and short text are slower to scan, but they preserve the shape of the disagreement.

The difficult sentence appears early

When two answers differ on noise, guests or cleaning, the brief says so. Early specificity is more useful than a harmony score that postpones the same discussion.

Danish sets the local detail

Writing in Danish first forced the scenarios to account for Copenhagen life: laundry-room booking, andelsbolig rules and the social choreography around shared meals. English remains available for people who need it.

Evidence boundary and next round

The public app and its production health endpoint are live. No paying users yet. The product can organise self-reported habits, housing facts and fit explanations across real product flows. It cannot yet demonstrate which pairings hold up over time. That requires a defined follow-up study rather than anecdotes dressed as match data.

The next useful evidence is a structured check-in after a viewing and again after a shared-home decision. Both sides should be able to say which early warning mattered, which one did not, and what the product failed to ask. Until that evidence exists, the portfolio makes no traction or compatibility-accuracy claim.

Decision dossiers, 2026

The current profile and room layers have grown beyond an early questionnaire concept. A complete dossier can carry monthly cost, timing, whole-home facts, daily rhythm, household expectations, fit signals, unknowns and viewing checks. Generated examples remain labelled and excluded from real inventory and matching.

The reasoning is developed in Sparse profiles need shelves. The related journal note, What Flatmate asks before two people share a kitchen, records the earlier compatibility model and its evidence boundary.

Open the product

• Open Flatmate.dk

Scope

Flatmate is a small matching product. It can move the first conversation from charisma toward daily rhythm. Housing supply, rent and landlord power remain outside its reach.