MiFisio Agenda

I co-founded MiFisio with Diego (a physiotherapist) and Jose (another engineer). Diego was spending half his week on admin instead of treating patients. Spreadsheets for scheduling, WhatsApp chaos for reminders, paper records he couldn't search. The tools on the market were either hospital-grade overkill or marketplaces that would sell his patients to competitors. So we built our own.

Today it serves 381+ physiotherapists who've managed 211,495+ sessions through the platform. Profitable with zero external funding, 92% annual retention. I lead product and engineering.

The Product

MiFisio handles the operational side of running a physiotherapy clinic. Physios don't need more features. They need fewer decisions. Most clinic software tries to do everything. We do the boring stuff so they don't have to.

• Agenda and online booking. Full calendar with drag-and-drop. Patients reserve 24/7 without phone calls. Clinics report gaining ~15 appointments/month just from the convenience.
• WhatsApp reminders. In Spain, everyone uses WhatsApp. SMS feels like spam. One-tap reminders from the session view. No-shows dropped 60% for clinics using it consistently.
• Billing and debt tracking. Invoices, payment history, bonds, packages. Dashboard shows who owes what at a glance. VeriFactu-ready for the 2026 mandate.
• Digital clinical histories. Replace paper folders. Searchable, accessible from any device. Mobile-first because physios check records between sessions on their phones.
• Analytics. Session counts, revenue, no-show rates, patient retention. The numbers you need to run your clinic without building spreadsheets.

Technical Decisions

Flask on the backend, Next.js on the frontend, Supabase for database and auth. Not the trendiest choices, but they let us move fast. Flask gives us control without framework magic. Next.js handles SSR for SEO on the marketing pages while keeping the app snappy. Supabase made sense because it's Postgres with auth and realtime built in, cheaper than Firebase, easier to migrate away from later.

We went with single-tenant architecture using shared tables. Each clinic gets their own instance, but the underlying database tables are shared across the platform. Row-level access control handles data isolation. Simpler than schema-per-tenant, easier to maintain, and RGPD compliance comes from proper access controls rather than physical separation.

The WhatsApp integration uses the official Business API through a third-party provider. We looked at building direct integration but the compliance requirements for healthcare data made a certified provider worth the cost. Messages are templated and approved by Meta. Less flexibility, but they actually get delivered.

Compliance shaped a lot of decisions. RGPD means data residency in the EU, explicit consent flows, right-to-deletion, audit logs. VeriFactu (Spain's electronic invoicing mandate for 2026) is built into the invoicing module. We didn't want to retrofit compliance later.

Everything runs in Docker on European infrastructure. 99.9% uptime with automated health checks and alerting. The whole system needs maybe an hour a week of maintenance. That was intentional. Three-person team means we can't afford ops eating into product work.

Go-to-Market

We bootstrapped with direct sales. Diego knew the market and had credibility. Early users came from his network and word-of-mouth in physio communities. No paid acquisition in year one. Every customer came from referrals or organic search.

Pricing is flat: 24€/month for everything, 22€/month annual. No per-user fees, no feature tiers, no usage limits. Competitors charge 20-150€/month with feature gates and VeriFactu as an upsell, some of them even take a cut on your patients. We wanted to be the obvious choice for physios who just want software that works.

The "made by physios, for physios" angle isn't just marketing. It's our moat. Diego catches UX issues that engineers miss because he uses the product daily with real patients. When we interview users, they mention that we "speak their language." We understand the workflow because we've lived it.

Partnerships helped scale without paid ads. We're now official partners with three Colegios Profesionales de Fisioterapeutas (professional associations in Madrid, Cantabria, Valencia). Industry partners include Fisiocampus (training), Fisiogestiona (consulting), Clínicas Zenit (franchise network). Credibility and distribution we couldn't have bought.

Results

Three years in, MiFisio has grown entirely through word-of-mouth and partnerships. The numbers tell the story:

• 381+ physiotherapists actively using the platform
• 211,495+ sessions managed
• 92% annual retention
• Profitable since month 12, entirely self-funded
• 60% drop in no-shows for clinics using WhatsApp reminders
• 5+ hours per week saved on admin per clinic
• Official partner with 3 professional associations and other leading entities

The impact that matters most is that physios get to focus on what they trained for. Less time chasing payments, less time on the phone scheduling, less time buried in paperwork. More time treating patients and growing their practice. Some clinics report saving 5+ hours per week on admin. Others see their no-shows drop significantly after switching to WhatsApp reminders. The specifics vary, but the pattern is consistent: MiFisio handles the operational overhead so they don't have to.

What I Learned

Vertical SaaS works when you truly understand the domain. We could've built generic "clinic software" and competed on features. Instead, we built physio-specific software and competed on fit. The specificity is the moat.

Having a domain expert as a co-founder changes everything. Diego isn't just our customer proxy. He's the filter that stops us from building the wrong thing. Every feature request goes through "would this actually help in a real clinic?" Half of them don't survive that question.

Bootstrapping forces discipline. When you can't raise money to paper over mistakes, you learn to validate before building. Our feature backlog is full of things we said no to. Most of them would have been wasted effort.

Compliance is a feature, not a burden. RGPD and VeriFactu compliance scared off competitors who didn't want to deal with them. We built compliance in from day one. Now it's a selling point instead of a scramble.

MiFisio continues to grow through referrals and partnerships. We're not chasing hypergrowth. We're building a sustainable business that solves a real problem for a specific audience. The kind of company I'd want to use myself.