Stage 1 of 7

Startup idea validation checklist: 25 milestones before you build anything

You have an idea. Maybe some notes, some research. But nothing concrete yet. Here’s how to know if it’s worth building.

4 min read24 milestones2 critical

Vibe coders can spin up an app in a weekend with Cursor or Lovable. That speed is a superpower and a trap. The most dangerous thing at Stage 1 is building. The most valuable thing is talking to people.

Most ideas die not because they are bad, but because they solve a problem nobody actually has. The gap between "interesting idea" and "real problem" is wider than most founders think. You close it with conversations, not code.

The most common pattern Banast detects in early-stage projects: a working prototype with zero user validation. A solution looking for a problem. This checklist exists to prevent that.

This framework is not about slowing you down. It is about making sure the thing you build fast is the right thing to build.

The key question at this stage: “Is this a real problem?”

Common trap: The builder trap: jumping to code before validating the problem. Vibe coders are especially vulnerable because building feels productive.

The checklist: 24 milestones

Product6
  • Problem identified and formulated in one sentenceCritical
  • Target user defined (who has this problem?)
  • Main use case described (job-to-be-done)
  • Existing alternatives listed (how do they cope without you?)
  • Hypothetical key differentiator formulated
  • V1 scope defined (what the product does AND does not do)
Tech3
  • Tech stack chosen
  • Technical feasibility validated (no major blocker)
  • Dev time estimate for a first prototype
Marketing & Distribution3
  • 3 target communities identified (Reddit, Discord, forums...)
  • Pitch wording tested informally (how do you explain it?)
  • Project name / domain reserved
Users & Validation4
  • 5+ exploratory conversations with potential targetsCritical
  • Problem validated by at least 3 people outside the network
  • Negative feedback received and integrated (not only positive)
  • Main persona documented
Business & Revenue3
  • Hypothetical monetization model defined
  • Market size estimated (even roughly)
  • Willingness to pay explored in interviews
Legal & Admin2
  • Verification that the name / domain is available
  • No regulatory blocker identified
Founder Mindset3
  • Able to explain the project in 30 seconds
  • Has identified own biases (builder trap, confirmation bias)
  • Time commitment defined (side project vs full time)

Category distribution

ProductTechMarketing & DistributionUsers & ValidationBusiness & RevenueLegal & AdminFounder Mindset
Stage 1: Idea

Think you’ve nailed Stage 1?

Most founders skip validation entirely. Banast analyzes your project across all 7 stages and flags exactly what is missing.

Frequently asked questions

How do I validate a startup idea without building anything?

Talk to 5+ potential users, identify the problem clearly, test willingness to pay in conversations, and list existing alternatives. The goal is signal, not code.

How many people should I talk to before building?

At minimum 5 exploratory conversations. At least 3 should be outside your personal network to avoid confirmation bias.

What is the builder trap?

The tendency to start coding before validating the problem. Especially common among developers and vibe coders who can ship fast. Building feels productive but delays the most important validation: does anyone actually have this problem?

Where does your project really stand?

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