Andrew Crossley

How do you build an MVP?

SHORT ANSWER

Build an MVP by picking one job a specific user will pay to have done, designing the single shortest flow that completes it, and shipping only that. Validate demand before building — interviews plus a paid or committed signal. A focused build can take four to six weeks; allow roughly six to twelve weeks from idea to public launch when validation, pilot users and fixes are included.

Answered by Andrew Crossley, AI Product Consultant & Product Partner · Updated 2026-08-01

Why it matters

Most first products fail on scope, not on code. Teams build six half-features instead of one that finishes a job.

An MVP exists to produce evidence. If it cannot change your mind about the business, it is not an MVP — it is a version one.

How it works in practice

  1. 1

    Write the one job

    One sentence: who, what outcome, in what situation. If it needs two sentences, the scope is already too wide.

  2. 2

    Validate before you build

    Ten to fifteen problem interviews plus a commitment signal — a deposit, a signed pilot, a waiting list with real intent.

  3. 3

    Design the single flow

    Map entry to outcome in the fewest steps. Every screen that does not sit on that path is out of scope for v1.

  4. 4

    Build with boring infrastructure

    Managed auth, managed database, hosted AI models. Custom infrastructure at MVP stage is capital spent on the wrong risk.

  5. 5

    Launch narrow and instrument

    Twenty to fifty users who match the profile exactly. Track activation, time-to-value and week-four return.

  6. 6

    Decide with the data

    Persevere, pivot the job, or stop. Set the thresholds before launch so the decision is not emotional.

Common mistakes

  • Building for a broad audience so nobody feels it was made for them.
  • Adding accounts, billing, admin panels and settings before anyone has completed the core job once.
  • Skipping instrumentation, then arguing about anecdotes after launch.
  • Treating an MVP as a smaller version of the eventual product rather than an experiment.

FROM EXPERIENCE

Cutting an MVP down to one flow

A typical first scope arrives with onboarding, dashboards, team accounts, notifications and reporting. Cutting to one flow — sign in, complete the job, see the result — usually removes 70% of the build and none of the learning.

At Wocal the version that mattered was the one that did a single thing end to end. Everything on the roadmap around it could wait, and most of it never needed building.

Frequently asked

How long should an MVP take?

A focused build should usually take about four to six weeks with modern tooling. From raw idea to public launch, allow roughly six to twelve weeks once validation, prototyping, pilot feedback and fixes are included.

Do I need a technical co-founder to build one?

No. AI-assisted build tools plus focused specialist help can get a first version live without an in-house engineer. Permanent engineering depth becomes more important as the product, customer data and operational complexity grow.

Should an MVP charge money?

Where possible, yes. Payment is the cleanest validation signal there is.

IN SHORT

  • One job, one flow, one user profile.
  • Validate with interviews plus a commitment signal before building.
  • Four to six weeks for a focused build; roughly six to twelve weeks from idea to public launch.

AI app development in six weeks

A validated, instrumented first product in front of real users.

AI app development in six weeks

THE FRAMEWORK

The Crossley Method: idea to first revenue in seven stages

See the full method
  1. STAGE 1DiscoverWeek 1
  2. STAGE 2ValidateWeek 2
  3. STAGE 3PrototypeWeek 3
  4. STAGE 4Build MVPWeeks 3-4
  5. STAGE 5LaunchWeek 5
  6. STAGE 6First RevenueWeek 6
  7. STAGE 7ScaleOngoing

MORE ANSWERS

Idea to MVP

How much does an MVP cost in the UK?

In the UK, a focused commercial MVP with one core user journey typically costs about £12,000–£25,000 with a product-led, AI-assisted build. A clickable or lightweight validation prototype can cost roughly £3,000–£8,000. Multiple user roles, complex integrations, RAG or agentic AI, specialist compliance or premium design can move the project above £25,000; larger agency builds can reach £60,000–£150,000.

How do you build an AI MVP?

Build an AI MVP by choosing one task where being right 80% of the time is still useful, wrapping a hosted model rather than training your own, and designing the interface around correction — users must be able to see, edit and accept output. Set an evaluation set before launch, measure task success and human-override rate, and only consider fine-tuning once the workflow itself is proven.

Can a non-technical founder build an AI app?

Yes. A non-technical founder can build and validate an AI app in 2026 using tools such as Lovable, Cursor or Bolt without first hiring a full engineering team. The founder still needs to own the customer problem, scope, accounts, data access, AI quality, costs and launch decision. Use specialists for the parts where a mistake creates real security, reliability or commercial risk.

What happens after building an app with Lovable?

After your Lovable app works, do not automatically rebuild it. First validate that real users want the core journey, then audit authentication and data access, billing, error handling, backups, monitoring, AI quality and cost per user. Fix launch blockers in risk order and add analytics before public release. Rebuild only when the existing architecture genuinely cannot support the business you have evidence for.