London consultancy combines grant writing, funding support and engineering to take mental health start-up from application to delivery

FatFish Digital, the London-based AI assurance, governance and engineering consultancy, has been appointed technology partner to Circe, the UK mental health start-up delivering therapist-led group sessions in a structured therapeutic format, following a successful Innovate UK grant application that FatFish helped to write.

The appointment marks the second half of a single engagement. FatFish worked alongside Circe's founders on the Innovate UK Biomedical Catalyst application, drafting the technical delivery and project management sections and aligning the build plan to the programme's milestones and evidence requirements. With the funding awarded, FatFish now moves into delivery. The project began on 1 September 2026 and will see Circe move off off-the-shelf tooling and onto a platform of its own.

From application to build

FatFish is unusual among engineering consultancies in supporting clients on the non-technical side of getting a product funded as well as building it. Alongside product design and engineering, the firm helps founders and scale-ups with:

• Grant applications, including Innovate UK, with a focus on making the technical and project management sections stand up to assessor scrutiny
• Fundraising support, preparing the technical due diligence, product roadmaps and delivery plans that investors expect to see
• R&D tax relief, identifying qualifying work and producing the technical narrative HMRC requires

For an early-stage company, these are often the difference between a good idea and a funded one. Circe has grown by bootstrapping and using non-dilutive funding wherever possible, and the Innovate UK award is its fourth successful grant.

What FatFish is building

Circe was founded by Claudia Radu and Gaurav Sood, with clinical leadership from Eva Papadopoulou and Dr. Jeanette Sundberg, and developed its early proposition through the Founders Factory programme. Having run multiple successful pilots, the company will leverage the platform build to serve paying customers, with the aim to expand into a B2B offer for employers, insurers and EAPs (Employee Assistance Programmes) in the future.

The platform FatFish is building covers:

• An intelligent matching engine that places each person in the right group, with a mandatory clinical screening step before anyone is enrolled
• Live group video sessions, booking and subscription billing
• Progress tracking and between-session work for participants
• Facilitator tools for the clinicians running each group
• An employer platform with anonymised, aggregate-only reporting
• Safeguarding, data protection and clinical sign-off designed into the product rather than bolted on afterwards

FatFish has been the technology partner to Welldoing.org, the UK's leading therapist-matching service, since 2013, and works primarily with NHS and healthtech organisations on AI assurance and governance.

David Lane, Founder and CEO of FatFish Digital, said:

"Most agencies turn up once the money is in the bank. We would rather be in the room when the application is written, because the plan that wins the grant is the plan we are held to for the next twelve months. Circe is a clinically-led model going online without losing the safety or judgement that make it work. That is exactly the kind of problem we exist for."

Claudia Radu, Co-founder of Circe, said:

"We needed a partner who takes the clinical side as seriously as we do. Working with FatFish ensures that our therapists and members get something designed around how group work actually happens."

Gaurav Sood, Co-founder of Circe, said:

“Partnering with FatFish has felt like a natural extension of our team. From day zero, they’ve been incredibly hands-on partners, from helping build the case for our Innovate UK project to brainstorming our product vision and supporting us on business development. We’re very excited to see this partnership evolve further on the back of a successful platform build."

About FatFish Digital

FatFish Digital is a London-based AI assurance, governance and engineering consultancy working with regulated organisations, primarily across the NHS and healthtech, with clients in financial services and legal. FatFish helps organisations design, build, assure and govern AI-enabled products, and supports founders with grant applications, R&D tax relief and fundraising readiness. https://fatfishdigital.co.uk/

About Circe

Circe delivers therapist-led online group programmes in a structured therapeutic format, giving people access to professional support alongside others facing similar challenges. Founded by Claudia Radu and Gaurav Sood, with clinical leads Eva Papadopoulou and Dr. Jeanette Sundberg, Circe is backed by Founders Factory and Innovate UK. https://hello-circe.com/

About Innovate UK

Innovate UK is the UK's national innovation agency and part of UK Research and Innovation. The Biomedical Catalyst supports UK businesses developing innovative healthcare solutions.