Anamnese completa / the full history

The story

I’m Guilherme Porto - Gui, or just Porto. I’m an engineer and founder from Rio de Janeiro. For the last twelve years I’ve been building software for doctors with the same co-founder, my college friend Gustavo Lima. This page is the long version of how that happened, told the way we tell everything around here: as a record.

História atual / present day (2014 → today)

Doutore is where I spend my days. The company took its name from its first product, and today it’s three products: Doutore (scheduling, electronic health records and financials for clinics), Dr. Assistente (an AI scribe that turns a consultation into a structured medical record in about thirty seconds), and SantoDoc (legally valid healthcare e-signatures without the digital certificate most patients don’t have).

Some facts about the company that I’m proud of:

  • Thousands of physicians and veterinarians use our products every single day - from a solo vet in a small town to some of the largest hospital networks in the country.
  • We are six people.
  • We’ve been profitable since 2015. We’ve never raised outside capital and never taken on debt.
  • Our support channel is, to this day, my personal phone number.
Porto and Gustavo writing product ideas all over the glass windows of an apartment
Anexo 01 · Gustavo and I, planning on the nearest writable surface. Some things never changed.

The company started in 2014, when the stress of a failing startup gave me bruxism, the bruxism broke one of my teeth, and the dentist who fixed it became our first paying customer - exactly one month after I showed her a mockup over lunch. Eleven years later she’s still a customer, and she knows she’s customer #1. I wrote that story down properly: The Dentist Who Started Two Companies.

The way we build hasn’t changed since that lunch: before we build anything, one of us becomes the product - the patient in the chair, the intern at the front desk, the human pretending to be the AI. The method has its own essay: Become the Product.

Antecedentes / two startups that failed (2013)

Doutore is our third company.

The first was carro.com.vc - an “Airbnb for cars” in Brazil. We won an international business-model competition at Santa Clara University with it, and it still failed: the entire model depended on an insurance product no Brazilian insurer offered. Along the way I emailed four US founders at addresses I guessed, got four replies within minutes, and flew to San Francisco for the most generous masterclass of my life.

The second was a carpooling project for university students. It went viral - 1,500 sign-ups in two weeks, national TV, a partnership with Rio’s city government - and earned exactly nothing. Validation isn’t revenue. Press isn’t revenue. Revenue is revenue.

I thank God both of them failed. The full road, including what each failure taught us, is here: Before Doutore.

Handing over car keys next to a carro.com.vc sticker on a black car
Anexo 02 · carro.com.vc, 2013: the keys to a stranger's car.
A wall of profile pictures from the carpool project's first 1,500 users
Anexo 03 · 1,500 sign-ups in two weeks: the carpool project's user wall.

Vida pregressa / the consulting years (2010 → 2012)

My first job was at K2 Achievements, a strategy consultancy, working on business restructuring and strategic planning for large Brazilian industrial companies. From there I went to Accenture’s strategy practice: credit operating models for Banco do Brasil, a petrochemical post-merger integration for Petrobras - and the strategic planning for Flamengo, which for a lifelong Flamengo fan barely counted as work.

In 2012 I left consulting to start companies with Gustavo. It took two failures and a broken tooth to find the right one.

Crowd watching as President Obama's helicopter lands at Flamengo's grounds
Anexo 04 · During the Flamengo project: the day Obama landed at the club.
Flamengo fans packed together welcoming Ronaldinho Gaúcho
Anexo 05 · Flamengo fans welcoming Ronaldinho Gaúcho.

Formação / robots, fuel cells, a master’s I never did (2005 → 2009)

I entered PUC-Rio at sixteen to study engineering. An intro course led me to the robotics lab, and the lab led me to RioBotz, the university’s combat-robotics team - almost two years of unpaid all-nighters that never felt like work. We became Brazilian champions, then world champions. The real prize was meeting Gustavo: twenty years later, we’re still on the same team. (That story: Twenty Years, Zero Titles.)

The RioBotz team posing with their big blue spinner robot at RoboGames
Anexo 06 · RioBotz at RoboGames: the team and the spinner.
Three RioBotz members giving thumbs up next to a stormtrooper at the competition
Anexo 07 · Pit-area diplomacy with the Empire.

Anexo 08 · RioBotz best hits (video)

I spent a year at the University of California, Irvine on a highly competitive exchange, working in a renewable-energy lab - work that was published as a scientific paper on micro PEM fuel cells. I took professional courses at MIT and was sure enough about academia that I applied for a master’s there. Then I spent one week working in consulting and understood I’d be happier building things in the real world. I never looked back.

A gloved hand holding a silicon wafer in the cleanroom at UC Irvine
Anexo 09 · UC Irvine cleanroom: the fuel-cell work that became a published paper.
MIT's Stata Center under a blue sky
Anexo 10 · MIT: the master's that lost to the real world.

História familiar / the personal one: Raynbow Baby

Not everything I build is for doctors - and this one isn’t part of the company at all. Raynbow Baby is mine alone: a project born at home, during our own long journey toward parenthood - the doctors, the exams, the loss, the learning. I built an AI platform that analyzes almost a hundred factors that can influence fertility - exams, health history, lifestyle, medication - and turns them into insights a couple can actually discuss with their doctor. It helped us see our own path more clearly, so I opened it, free, to other couples walking the same road. It doesn’t replace doctors and it has no business model, on purpose.

It’s not for making money. It’s for making humans.

Conduta / say hi

The best way to reach me is email: porto@doutore.com. I live by inbox zero - you’ll hear back within a day.

Registro aberto em 2014 · it all started with a broken tooth 🦷 read the story

© 2026 Guilherme Porto · Brazil

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