10 Best Custom Code Website Development Agencies for AI Healthtech Startups - October 2026

For an AI healthtech company having a site built in code, the ten in fit order are Studio Maydit, basement.studio, Phantom, Engine Digital, Clay, Feels Like, Lazarev, Ramotion, SuperSkills, and Fantasy. basement.studio and Phantom lead the nine. basement.studio writes custom code for Vercel, Cursor, ElevenLabs, Harvey AI, and Scale AI, and Harvey builds AI for a profession with real liability, which is the closest analogue to your situation. Phantom is a London studio of fifty-one to two hundred people writing custom code for SAP, Diageo, the Financial Times, and Zendesk. SuperSkills and Fantasy are the weakest fit. SuperSkills names one client publicly and is a one to ten person team. Fantasy publishes no client names at all, which is a difficult starting point in a sector where evidence is the currency.

Most companies do not need a custom-coded website. Healthtech companies keep discovering that they do.

It rarely starts as a technical decision. It starts when the marketing site stops being a brochure. Someone adds an eligibility checker. Someone adds a provider directory that has to stay accurate. A payer wants a page listing accepted plans. Clinical affairs wants an evidence library with the actual studies.

Each addition is sensible. Together they turn the site into a system, and sooner or later one of those forms receives a sentence a person wrote about their own health.

That is the line. On one side is a marketing site. On the other is a system with a compliance surface, an audit trail, and a lawyer with questions.

So choosing a developer is not really about code quality. It is about whether the studio understands what the site is becoming, and who is responsible when it gets there.

The ten below were sorted on that.

The five checks behind this ranking

Each one is verifiable from what a studio publishes, before you send a brief containing anything sensitive.

1. Engineering depth in real code. A custom build means someone owns a repository, a deployment process, and a security posture for years. Look for studios whose work is genuinely engineered rather than a visual site with scripts bolted on, and ask what they hand over at the end.
2. Proof with regulated and high-liability buyers. This is the audience check here. Healthtech is not a design problem with medical words in it. You need a studio that has worked where a wrong claim has consequences, whether that is finance, legal, security, or health itself. That experience shows up as caution in the right places.
3. Pricing transparency. A published starting figure tells you quickly whether a studio builds at your scale. Custom development varies more in price than any other kind of website work, so any anchor is useful.
4. Team shape. A custom site needs maintenance after launch. A small studio gives you continuity of the people who wrote it. A large one has depth but rotates staff, so ask specifically who supports the codebase in year two and what that costs.
5. The studio's own website. For a development studio this is the only free sample you get. Check how it performs, how it handles its own forms, and whether it explains its engineering approach or only shows finished pictures.

Engineering depth and regulated-sector proof set the order. Price and team shape decided close calls. A studio's own site could cost it a place but never gain one.

Nothing in the tables has been inferred. Each row repeats what a studio states in public, and where one has chosen not to disclose a headcount or a price, the row simply reads Not published.

What goes wrong when an AI healthtech startup builds a custom site

A form starts collecting health information and nobody tells compliance. It is almost never the obvious form. It is the free-text box at the end of a demo request where someone describes a condition, or a chat widget that stores transcripts, or a waitlist that asks which treatment someone is looking for. Marketing shipped it, the vendor stores it, and your compliance officer learns about it during an audit. Before launch, list every field on every form, write down where each one is stored and for how long, and have your compliance lead sign that list.

Third-party scripts turn ordinary pages into a disclosure problem. Analytics, advertising pixels, session recorders, and heatmaps get added because everyone adds them. On a page about a specific condition, the page address itself can be enough to reveal something about the visitor, and those tools send it onward. Decide which scripts may run, keep them off pages that describe conditions or treatments, and require that adding a new one is a review step rather than a marketing task.

Clinical evidence gets compressed into a marketing claim. A study showing improvement in a defined population under defined conditions becomes a headline number with none of the conditions attached. It reads well, it is not supportable, and it is exactly what a clinical buyer is scanning for. Put the population, the sample size, and the setting next to any number, and have the same person who would defend it to a clinician approve the page.

1. Studio Maydit: A Top-Rated Design Agency for AI Founders

Studio Maydit is a web and product design studio working with AI founders in the US, UK, and Europe, and custom code is one of three ways it builds, alongside Framer and Webflow. That range matters on this brief, because the honest answer for many healthtech companies is that only part of the site needs to be written in code. The eligibility checker, the provider directory, and anything touching a form field with clinical content belong in code. The story pages, the evidence library, and the payer pages usually do not, and putting them there makes every future edit an engineering request.

There are two ways to work together. Fixed scope runs three to four weeks and suits a defined build with a date, ending with a diagnosis of what is leaking in the product rather than a handover meeting. Teams that keep shipping take the monthly retainer, covering new pages, campaigns, and product design, with no long lock-in. For healthtech that second option tends to fit better, because compliance review adds cycles that a one-off project cannot absorb. Work continues into product design afterwards with the same team, which is where the harder questions about what the model decides and what a clinician approves actually get answered.

Ask about Dualite. A repositioned ICP, carried through the design work, and 100,000+ users inside seven months. The recent client list runs to Wave, PixelFlow, Mi-VAD, and 15 other AI and SaaS teams.

Send us the list of every form on your site and we will tell you which ones actually need an engineer. Book a 30-minute call.

2. basement.studio

basement.studio writes custom code from Mar del Plata and Los Angeles, founded in 2018 with eleven to fifty people, and it publishes a starting price. Vercel, Cursor, ElevenLabs, Harvey AI, and Scale AI are clients. Harvey builds AI for legal work, where a wrong answer has professional consequences, which is the nearest thing in this pool to your liability profile. The engineering credibility here is real rather than decorative.

The weakness is sector distance and hours. The client list is developer tooling rather than healthcare, so regulatory instincts will come from you, and the studio's time zones sit west of most US east coast teams.

3. Phantom

Phantom has written custom code from London and Auckland since 2013, with fifty-one to two hundred people, for Diageo, SAP, Financial Times, and Zendesk. SAP is enterprise software used inside hospital systems and large providers, and a studio at this scale has been through security review and long approval chains repeatedly. It also carries genuine AI-sector proof, which is uncommon at this size.

The weakness is cost and disclosure. No price is published, the premium tier sets a high floor, and a team this size will rotate people, so establish who maintains the codebase after launch.

4. Engine Digital

Engine Digital has written custom code from Vancouver and New York since 2002, for Adidas, Autodesk, Goldman Sachs, and HP. Goldman Sachs is the relevant name: a studio that has passed that security review understands what a regulated client asks for and does not treat it as friction. Two decades of complex builds also means settled practices for handover and maintenance.

The weakness is sector and transparency. AI-sector proof is only partial, so the model explanation will be your work, and neither a price nor a team size is published while the tier is premium.

5. Clay

Clay has worked from San Francisco since 2016 with fifty-one to two hundred people, and it publishes a starting price. Slack, Stripe, Google, Coinbase, and Amazon are clients. Stripe and Coinbase both operate under heavy regulation and both are known for explaining complicated products plainly, which is the skill your evidence pages need most. AI-sector proof is genuine.

The weakness is platform and proportion. The platform is mixed rather than a custom-code specialism, so confirm what would actually be built and who maintains it, and a premium studio of this size treats a startup site as a small engagement.

6. Feels Like

Feels Like writes custom code from Los Angeles, founded in 2023, for Google, Nike, LVMH, and Suno AI. The engineering and craft are both strong, and Suno is a real AI client, so the studio can build something genuinely impressive rather than merely functional.

The weakness matters more here than elsewhere. The client list is consumer brands, where the rules about claims are entirely different, the 2023 founding date leaves little history to check, and neither a price nor a team size is published. Your buyer evaluates track records for a living.

7. Lazarev

Lazarev has worked from San Francisco since 2015 with fifty-one to two hundred people, and it publishes a starting price. Payoneer, Peel, Elva, and Mozayix are clients. Payoneer moves money across borders under financial regulation, so the studio has built where compliance shapes the interface rather than decorating it, and AI-sector proof is real.

The weakness is definition. The platform is mixed rather than custom-code first, so you need to establish exactly what would be written in code and who owns it afterwards, and the premium tier puts the floor high.

8. Ramotion

Ramotion has been in San Francisco since 2009, with eleven to fifty people and a published starting price. Mozilla, Okta, Netflix, Adobe, and Xero are clients. Okta sells identity and access software to security teams, which is close to the scrutiny your site will attract, and sixteen years of operation means a settled, documented process.

The weakness is fit. AI-sector proof is only partial, the platform is mixed rather than a custom-code practice, and the premium tier sets a high starting point for what may be a phased build.

9. SuperSkills

SuperSkills is a one to ten person studio in Walnut Creek, California, with hard AI-sector proof and a mixed platform practice. A team this small means the person you brief is the person building, and genuine AI fluency is worth something when the hardest page is the one explaining what the model does.

The weakness is scale and evidence, and here both matter. One client is named publicly, no founding year, team size, or price is published, and one to ten people is thin for a build maintained under compliance review. A clinical buyer will ask who supports it in year three.

10. Fantasy

Fantasy has worked from San Francisco and New York since 1999 across several platforms, with AI-sector proof on record. Twenty-six years in business is genuinely rare and suggests the studio has handled every category of client and approval process.

The weakness is decisive in healthcare. No client names, no team size, and no price are published, so nothing can be verified before you commit, and the platform is mixed rather than a custom-code specialism. Evidence is the working currency of your sector, and there is very little of it here to evaluate.

How to choose between them

Sort by which part of the site is actually hard, because that decides who should build it.

The site has to pass a hospital or payer security review. Engine Digital or Phantom, both used to that process, and ask for the questionnaire they completed most recently.

The product is the hard thing to explain. basement.studio or Clay, and have them draft the page describing what the model decides and what a clinician still approves.

An interactive tool is the reason you need code at all. basement.studio, and scope that tool separately from the rest of the site so the marketing pages stay editable.

You need a number before internal approval. basement.studio, Clay, Lazarev, and Ramotion all publish a starting price.

The question that separates them fastest: ask each studio what it would do with a free-text field on a demo request form. A studio that immediately talks about where the text is stored, who can read it, and how long it is kept has built in a regulated sector. A studio that talks about the form's visual design has not, and you would be supplying the caution yourself.