Vouch
The method

FeDeVi: three lenses, ranked assumptions, repeatable evidence.

A customer-validation framework borrowed from the discovery world and refined for product builders. Vouch is built around it natively — no template gymnastics, no spreadsheets.

DE

Desirable

Do they actually want it?

VI

Viable

Can it be a business?

FE

Feasible

Can you build it?

DE

Desirable

The hardest lens, and the one most teams skip. Find out whether the problem is even worth solving — before you write a roadmap, before you talk to engineering.

Signals you've validated this lens

  • Customers describe the pain in their own words, unprompted.
  • They've tried — and abandoned — at least one workaround.
  • They can point at a moment last week when it cost them money or sleep.
VI

Viable

Desire isn't enough. The economics must work. This is where you test pricing, channels, willingness to pay, and the unit math.

Signals you've validated this lens

  • Real numbers from real budgets — not hypothetical price ranges.
  • A clear buyer (not just a user) and a path to reach them.
  • Margins survive after CAC, support, and the parts you forgot.
FE

Feasible

The cheapest lens to test, and the easiest to overweight. Engineers love this question. Don't let it drown out the other two.

Signals you've validated this lens

  • A working prototype path that doesn't need a PhD.
  • Latency, cost and reliability budgets that close on a back-of-envelope.
  • No dependency that could vanish at a vendor's whim.
Operating principles
01

Rank, don't list.

Twenty assumptions in a doc is procrastination. Three ranked by importance × evidence is a plan.

02

Talk to humans.

Surveys flatten signal. Conversations expose triggers, jargon and the workaround they're already paying for.

03

Synthesize at five.

Five interviews is enough to update beliefs. Ten without synthesis is a backlog you'll never read.

04

Kill quickly.

The point of validation isn't to build. It's to know what not to build. Killing an idea in two weeks is a win.

05

Pilot before you ship.

A learning-focused pilot replaces a quarter of arguing about the spec. Send it on Monday.

Run the method without the busywork.

Vouch handles the ranking, the live interview coaching, and the synthesis. You bring the curiosity.