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For founders with early customers and funding

Turn your early product into a platform ready to grow.

Senior product and engineering support for founders with early customers and funding. We assess what you have built, identify the risks, and help you plan the next stage.

Request a free introductory callWe will contact you to arrange it.

Start with a Launch Readiness Review: £3,500 + VAT.

A founder partnership

Grant support is complete. The platform is in progress.

Circe is a therapist-led mental health start-up. The founders had run pilots and were applying for Innovate UK funding. FatFish drafted the technical delivery and project-management sections of the Biomedical Catalyst application with them. The funding was awarded. Delivery started on 1 September 2026: Circe is moving off off-the-shelf tools onto its own platform. That build is underway. It is not a completed launch.

Read the announcement (opens in a new tab)

Request a free introductory call

The stretch from early customers to the next stage is where founders get stuck.

It works for the first customers.

The open question is how it will behave with more users, an investor’s questions, or a customer’s security review.

The risks are rarely the features.

Authentication, payments, data protection, accessibility and deployment often decide whether the next stage is a sound step.

A bigger build is the wrong first commitment.

You need to know what to keep, what to change, and what not to build yet.

One standard offer

Launch Readiness Review

A focused assessment of one early-stage product, within an agreed technical scope.

Fixed fee

Launch Readiness Review — £3,500 + VAT fixed fee.

Larger or more complex reviews start from £6,500 + VAT. We agree the scope and exact fee before work begins. Expanded scope may be needed for multiple applications, substantial integrations, sensitive data, complex payments or permissions, detailed migration planning, or a specialist AI assessment. A health-related product is not automatically an expanded review. We determine the scope before quoting.

Not included

  • Fixing the issues found.
  • Exhaustive testing or complete code coverage.
  • Formal penetration testing.
  • Legal advice or compliance certification.
  • Full UX research.
  • A complete build specification.

Follow-on work is scoped and priced separately. You are under no obligation to commission it.

Request a free introductory call

What £3,500 includes

01A founder kickoff covering the product, traction, users, constraints and the next decision.
02An architecture review, and a review of selected business-critical code paths.
03Checks on authentication, authorisation, secrets, dependencies and the relevant data flows.
04A look at deployment, monitoring, backups and obvious scaling constraints.
05A recommendation to keep, harden, refactor or rebuild.
06Plain-English findings, prioritised actions and an estimated delivery roadmap, with the assumptions stated.
07A findings walkthrough and a report you can use with another supplier.

After the review

How the work is judged, then quoted.

Our senior team will review the product you already have, say what to do first and what not to build yet, and stage the investment. Production work, ongoing support, grant applications and fundraising are quoted separately. Nothing in the review is an unlimited retainer.

Production

Delivery, quoted after the review

Our senior product and engineering team can carry out the prioritised plan, keeping what should stay and changing what should not. You see the scope and the fee before that work starts. You do not have to commission it.

Support

Further help, as a defined engagement

Product and engineering support after launch can be agreed later. It is a separate piece of work, not unlimited engineering or maintenance, and it is not included in the review fee.

Additional

Grants and fundraising, when you need them

Help with grant applications, fundraising materials and R&D tax claims is available as further work. It does not guarantee funding, and it is not part of the review.

Work

Early products we have taken further.

A person practising yoga on a mountain ridge

Welldoing

Starting situation
Welldoing’s directory of therapists, counsellors and coaches had outgrown its platform. The existing system could not support the growth the organisation needed.
FatFish’s role
FatFish defined requirements with the Welldoing team, prioritised the work and set a phased roadmap.
Work completed
The platform was rebuilt in phases, with a scalable backend and improvements to performance and usability.
Outcome
Welldoing now runs a live platform that supports higher demand, with faster load times and a base for further optimisation.
Read the Welldoing case study (opens in a new tab)
A clinician showing a tablet to a patient

Thriving Clinics

Starting situation
A partnership of Cheshire GP practices needed a public site for private care, starting with a doctor-led weight-loss service, that still felt like the surgery patients already trust.
FatFish’s role
FatFish mapped the patient journey before building, and treated booking as part of the site rather than a link in the footer.
Work completed
FatFish designed and built the public website, including service, location and team pages, with Cliniko booking built in.
Outcome
The site is live at thrivinggp.co.uk and is structured so further services and sites can be added. Cliniko booking is built in and launching shortly.
Read the Thriving Clinics case study (opens in a new tab)
A brown dog running on a beach

Animor

Starting situation
Animor wanted a membership community for pet owners on web and mobile. The idea did not yet have the technical foundation for a growing user base.
FatFish’s role
FatFish worked with the Animor team to define the product vision and the main user journeys.
Work completed
The platform was built from the ground up, including the backend, the interfaces, and membership and community features.
Outcome
Animor has a live platform that supports an active community of pet owners, and a base for further features.
Read the Animor case study (opens in a new tab)
Dr Andrew Wilson
FatFish understood what we were trying to build from the first conversation - a private service that still feels like the GP practice our patients already trust. They delivered a polished site and embedded Cliniko booking so people can arrange a free chat without leaving the page. The integration just works - and the team kept clinical workflow at the centre throughout.
Dr Andrew WilsonFounding Director, Thriving Clinics

A typical fit

Founders with an early product, early customers, and funding or an allocated product-development budget. You want senior product and engineering judgement, and you are willing to invest in stages rather than commission a large build on day one.

Usually not a fit

You want the cheapest possible build to a fixed specification, or you would rather not hear that part of the plan needs to change.

Founders usually ask

Do I need a technical co-founder first?

No. We can provide senior product and engineering support, and help you decide whether and when to hire.

Can you work with code generated by Lovable, Bolt or Cursor?

Yes. The review tells you what is worth keeping and what needs rebuilding before the next customers arrive.

What does the review cost?

The standard offer is a Launch Readiness Review — £3,500 + VAT fixed fee, for one early-stage product within an agreed technical scope. Larger or more complex reviews start from £6,500 + VAT. We agree the scope and exact fee before work begins. Expanded scope may be needed for multiple applications, substantial integrations, sensitive data, complex payments or permissions, detailed migration planning, or a specialist AI assessment. A health-related product is not automatically an expanded review. Production work after the review is quoted separately, and you are under no obligation to commission it.

What is not included?

The review does not include fixing the issues found, exhaustive testing or complete code coverage, formal penetration testing, legal advice or compliance certification, full UX research, or a complete build specification.

Does the form book the call?

No. Request a free introductory call and the team will contact you to arrange it.

Can you help with grants or fundraising?

Yes, as additional work. Grant applications, fundraising support and R&D tax claims are not included in the review, and they do not guarantee funding.

Do you work outside the UK?

Yes. We are London-based and work with founders elsewhere too.

The team

People who do this work.

The team will contact you to arrange the introductory call.

  • David Lane

    David Lane

    Co-Founder & CEO

    Founded FatFish Digital in 2013 and has architected more than 100 products.

  • David Caswell

    David Caswell

    Co-Founder & Chairman

    Marketplace and health-tech specialist. Co-founded Rated People, and chairs Welldoing.org and Carradale Futures.

  • Owais Nizam

    Owais Nizam

    Tech Lead

    Software architect and engineer. Leads full-stack and AI-driven delivery, including data pipelines, APIs and cloud infrastructure.

  • Philip Bowden

    Philip Bowden

    Product Owner

    Product lead. Guided Welldoing’s platform rebuild across requirements, timelines and releases.

Request a free introductory call.

Tell us about the product, the early customers and the decision in front of you. The team will contact you to arrange the call.

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