selected work / software & systems

Portfolio

00 Anno Domini / ERP
ERP · clinic management
Anno Domini
- React
- JavaScript
- Node.js
- MongoDB
- Socket.IO
- Metabase
Anno Domini is a business operations platform used across three companies in Brazil. At the medical clinic, it manages the complete patient workflow from scheduling and reception through consultation and payment, connecting operational, clinical and financial data in a single system.
implementation details
The platform includes scheduling, check-in, doctor queues, patient records, prescriptions, payments, financial operations and administration, with separate role-based interfaces for receptionists, doctors and administrators.
Key engineering work includes server-side scheduling conflict validation, idempotent check-in flows that prevent duplicate visits or charges, role-based authorization, audit trails and financial operations supporting split payments across cash, Pix and cards while preserving a correction history.
The platform also includes patient- and appointment-linked internal conversations with real-time Socket.IO notifications and optional Metabase analytics through sanitized read-only MongoDB views and signed embeds. It supports self-hosted deployment on the clinic’s own infrastructure.
read case study
01 GridScope / historical demo
data & analytics · Danish electricity carbon intensity
GridScope
- Python
- PostgreSQL
- FastAPI
- Dagster
- React
- TypeScript
An electricity carbon-intensity analytics platform built with Python, PostgreSQL and React. Processes five-minute Energinet observations for Denmark’s DK1 and DK2 regions, with validated ingestion, SQL reporting, data-quality checks and interactive visualizations.
implementation details
The full application includes FastAPI, PostgreSQL and Dagster orchestration. Ingestion uses transactions and PostgreSQL advisory locks; reporting checks missing intervals, UTC alignment and Europe/Copenhagen daylight saving time.
The public demo is a static React application on Cloudflare Pages using real historical observations from October 9, 2026. It has no live backend or real-time data feed.
read case study source code live demo
```
const request: ReportRequest = {
  employeeIds: [id],
  start: interval.start,
  end: interval.end,
  format: "PDF",
  report: "extrato_banco_horas",
  saldoBanco: "TODOS"
};

const { guid } = await client.requestReport(request);
await client.waitForReport(guid);
```
02 src/index.ts · exportEmployeeFromAdmission
automation · attendance and hour-bank records
RHID Historical Attendance Exporter
- TypeScript
- Node.js
- Playwright
- CSV / PDF
RHID Historical Attendance Exporter was developed to recover and consolidate more than five years of employee attendance and hour-bank history for a medical clinic. During the project, I investigated RHID’s authenticated network requests to access historical records that were difficult to retrieve through the standard interface, and identified discrepancies between some native reports and the underlying daily attendance records.
implementation details
The exporter uses the daily records as the primary source for structured CSV and locally generated PDF reports.
It processes each employee’s history from their admission date, splits large requests into configurable date ranges for reliability and preserves RHID’s original reported balance alongside a balance calculated from the underlying daily records.
Authentication and protected requests are automated with Playwright using authorized clinic access.
source
03 project artwork
web application · training and nutrition
ilovediana.org
- React
- Tailwind CSS
- Node.js
- Express
- MongoDB
- Cypress
- Supertest
An archive for documenting training, nutrition, progress photos and notes over time. Public protocols can be searched and shared; private records remain accessible only to their owner. Each protocol has its own page and can be printed or saved as a PDF.
implementation details
The API checks ownership and visibility before reading or changing records. Uploads validate file contents as well as extensions. Security tests cover unauthorized access to private protocols, forged ownership, XSS and image validation.
source visit site

Anno Domini

GridScope

RHID Historical Attendance Exporter

ilovediana.org