Personal dossier

João Vitor

I build the systems that keep Brazilian public healthcare running.

Halftone portrait of João Vitor
JOÃO VITOR CAVALCANTI DA SILVA
Role
Full Stack Developer
Based in
Caruaru, PE
Since
2023
Status
Open to talk about projects
01Manifesto

Software nobody can afford to see break.

I don’t build pretty landing pages nobody uses.

I build systems a health department opens at 7am that simply cannot fail.

Where one wrong number in a report is federal funding a town never receives.

Where the queue at the front desk depends on a WebSocket I wrote.

That changes how you write code.

You stop asking “does this work?” and start asking “will this hold?”.

Three years of it. Ten systems in production. Not one boring day.

02Work

One large project beats ten small ones

Ten systems in production for two clients: the public healthcare ecosystem running across more than 400 municipalities, and consumer products where the hard part is integrity. All of them proprietary code — so what I show here is how each one was built, which problem it solves and which part is mine.

The ecosystem in numbers

400+

municipalities served

200+

screens in production

50+

API route modules

300+

database migrations

7

systems under the hub

Counted in the ecosystem’s code — R-SUS, Surveillance and the portal — and rounded down.

01

e-Gestão

The hub of a public healthcare ecosystem

Not a system — the single portal a health department logs into to reach all of them: primary-care reporting, citizen portal, health surveillance, BPA, call panel and an AI assistant. Multi-tenant by municipal IBGE code, in use across more than 400 municipalities in 26 states. The largest project I work on, and the one that taught me the most.

TypeScriptNext.jsReactTanStack QueryTailwind CSSExpressFastifyKnexPostgreSQLRedisBullSocket.IOPuppeteerOllama · RAGJWTAWS S3NginxPM2Linux
View live(opens in a new tab)

Proprietary code. Private client system — the repository isn’t public.

My role
Full stack developer · project delivery · database and infrastructure
Client
Wi Consultoria
Sector
Municipal public health · Brazil
Period
2023 — present
Status
In production

The other cases

Different domains, the same demand. Each has its own case.
02In production

Painel de Chamadas

Real-time patient calling

The waiting-room TV calls the patient by name, out loud, the moment the professional clicks inside e-SUS itself. Four pieces talking to each other — a browser extension, a WebSocket server, the TV panel and the API — without touching a single line of PEC’s code.

  • TypeScript
  • React
  • Next.js
  • Fastify
  • WebSocket
Open case
03In production

Roleta Online

Quota-based draw with limited seats

You come in, buy chips, and each chip is a seat on the wheel. When the wheel fills — 20, 40 or 100 entrants depending on the type — the draw runs and one winner comes out. Simple to describe and full of concurrency traps: real money, limited seats, and a result people have to trust.

  • TypeScript
  • Next.js
  • React
  • Node.js
  • PostgreSQL
Open case
04In production

Bolão de Futebol

Predictions, scoring and ranking

A tournament pool: entrants predict the round’s results, the system scores them once matches end, and the leaderboard updates. The challenge isn’t adding points — it’s the deadline, the scoring rule that changes between tournaments, and results that sometimes get corrected after the fact.

  • TypeScript
  • Next.js
  • React
  • Node.js
  • PostgreSQL
Open case
05In production

Dodreams

From dream to plan

A place to record and manage dreams — a trip, an achievement, a long-term goal — and turn each one into something with steps, a deadline and progress. The difference between “someday I want to” and a plan you can actually track.

  • TypeScript
  • Next.js
  • React
  • Tailwind CSS
  • Node.js
Open case

+Each card opens a full case.

Also in production

Real deliveries, no case page
  • 06

    R-SUS

    Primary-care reporting

    Wi Consultoria
  • 07

    SUS Direto

    Citizen portal

    Wi Consultoria
  • 08

    Visa

    Municipal health surveillance

    Wi Consultoria
  • 09

    BPA Online

    Outpatient production to the official file

    Wi Consultoria
  • 10

    RAID

    Inherited clinical management, kept alive

    Wi Consultoria

Systems in production that I built or maintain, listed without a dossier of their own: five more dossiers from the same ecosystem would read as repetition, not depth. If you want the detail on any of them, ask.

03Clients

A company of my own, and the people who trust me with theirs

Two different things, and I don’t blur them: Quiral Labs is my own company. Wi Consultoria and Catsuc Labs are clients — people who hired me to build what can’t fail.

My companyquirallabs.com.br
Quiral LabsCustom software and 3D printing

My own company. Custom software and 3D printing — where the work I build carries my name.

(opens in a new tab)

Who hires me

2 clients
04Arsenal

A tool is a choice, not an identity

No percentage bars. Just where the tool actually sits: in production every day, shipped with it, or studying it right now.

DepthDaily productionShipped with itStudying
01

Language

TypeScript end to end. The rest shows up when the problem asks for it.

  • TypeScript
  • JavaScript
  • SQL
  • Python
  • C
  • PHP
  • Java
02

Interface

200+ report screens taught me consistency beats loose creativity.

  • React
  • Next.js
  • Tailwind CSS
  • TanStack Query
  • shadcn/ui · Radix
  • React Hook Form · Zod
  • Recharts
  • Vue.js
  • GSAP
03

Server

APIs carrying sync pipelines, exports and queues. Express where it’s mature, Fastify where it’s new.

  • Node.js
  • Express
  • Fastify
  • Knex
  • Prisma
  • Bull · queues
  • WebSocket · Socket.IO
  • REST
  • Puppeteer
04

Data

Modeling, indexes and execution plans. A slow query in a health report is not a detail.

  • PostgreSQL
  • Redis
  • MySQL
  • Migrations
  • ETL · sync
05

AI & Automation

Not hype: I built the agent harness that orchestrates development across ten products here, and shipped a RAG assistant into production inside a healthcare system.

  • Agent harness
  • Claude Code
  • Cursor · Composer
  • Context engineering
  • RAG
  • Self-hosted LLM · Ollama
  • MCP
  • Process automation
06

Infra & Ops

I deploy it, I harden it, I get up if it falls. AWS Academy certified in cloud architecting.

  • Linux · VPS
  • Nginx
  • PM2
  • Docker
  • AWS · S3
  • Google Cloud
  • Git · CI/CD
  • VPN · hardening
05Trajectory

How I got here

No job titles here — just how I learned. The rail below is the narrative; the certificates at the end are the receipts.

  1. Jan 2025 — now

    Study

    Computer Science

    InstitutionUniFavip WydenCaruaru, PE

    Degree in progress. Data structures in C, algorithms and complexity — the fundamentals practice leans on daily without ever naming them.

    • C
    • Estrutura de dados
    • Algoritmos
    • Complexidade
    1

  2. 2025

    Study

    Cloud and security, formalised

    AWS Academy · Cisco

    Cloud architecting and cloud foundations through AWS Academy, plus cyber threat management through Cisco. I was already deploying and hardening servers; this was about learning the names for what I was doing — and what I was doing wrong.

    • AWS
    • Arquitetura em nuvem
    • Segurança
    • Redes
    2

  3. 2025

    Study

    Full Stack Week

    Full Stack Week

    An intensive week building a full stack project end to end. Less about syntax and more about watching someone else make architecture decisions in real time.

    • Next.js
    • Prisma
    • Arquitetura
    3

  4. 2023

    Study

    JavaScript, properly

    Hashtag Treinamentos

    A JavaScript intensive in the same year I took on my first production system. Learning the language while it was already running for someone else changes how closely you pay attention.

    • JavaScript
    • DOM
    • Assíncrono
    4

  5. 2022

    Milestone

    Where it started, on my own

    Udemy · Rocketseat

    Two long courses on web development and React, done alone with nobody checking. Enough to get into the industry the following year — and the part of the story I defend hardest.

    • HTML
    • CSS
    • JavaScript
    • React
    5

Certifications and courses

Seven certificates. The ones that matter are on top.
2025Certificate

Cloud Architecting

AWS Academy

2025Certificate

Cloud Foundations

AWS Academy

2025Certificate

Cyber Threat Management

Cisco

2025Course

Full Stack Week

Full Stack Week

2023Certificate

JavaScript Intensive

Hashtag Treinamentos

2022Course

React from Zero to Mastery — hooks, router, API

Udemy

2022Course

Complete Web Development — 6 projects

Udemy

06Signals

Live from GitHub

Fetched straight from the public GitHub API when this page is served.

Public repositories

23

Followers

12

On GitHub since

Aug 10, 2023

Most used languages

  • TypeScript7 · 33%
  • JavaScript4 · 19%
  • HTML3 · 14%
  • Python3 · 14%
  • C2 · 10%
  • Java1 · 5%

Recently pushed

View GitHub profile
07Off the editor

The person behind the commit

Local time in Caruaru

--:--:--▌

Based in

Caruaru, PE

The agreste of Pernambuco, capital of forró. You can build serious software 130 km inland — and I prefer it that way.

How I work

Context before code

I read the domain before opening the editor. You don’t guess public-health business rules: if I haven’t understood the technical note, the code will be wrong and pretty.

Current obsession

Types that don’t lie

TypeScript taken seriously, from the database schema to the component. If it compiles and still breaks, the type was too loose.

Learning now

Architecture and scale

Cloud, observability, and what separates a system that works from one that survives growing tenfold.

Languages

Portuguese · English

Native Portuguese. Intermediate English — I read docs, specs and RFCs without a translator.

Away from the editorUTC−3

-8.2837° S
35.9760° W

Caruaru, Pernambuco — Brazil

08Terminal

Rather ask it yourself?

A real terminal, with real data. Everything in here is also written above — this is a shortcut, not a gate.

joaovitorkc.com.br — dossierType help and hit Enter
09Contact

Let’s talk

New project, a role, or just a question about how e-Gestão solves something — reach out.

Open to talk about projects

Direct

Emailjoaovitorrkc@gmail.com
WhatsApp+55 (81) 98212-0328(opens in a new tab)
GitHub@joaovitorkc(opens in a new tab)
LinkedIn/in/joaovitorkc(opens in a new tab)
Instagram@joaovitork.c(opens in a new tab)

Or write here

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