Selected Projects

Two case studies with the problem, my contribution, the confirmed stack and how each one can be verified.

Both cases evidence the software engineering axis. The data engineering axis is evidenced by professional work — relational modelling, query and index tuning, ETL with SSIS and system integration — described under Experience. A dedicated data engineering case study is not published yet.

Experience

On Line Engenharia de Sistemas logo

On Line Engenharia de Sistemas Software house serving public registry offices (cartórios) in Brazil · Cuiabá, MT

Computer Applications Engineer (CONFEA/CREA)

September 2025 — present

  • Lead the development lifecycle as the engineer of record: translate business needs into technical requirements and design system architectures for scalability and maintainability.
  • Build production features in Go, Delphi, Python and the web stack, with test and deployment routines before each release.
  • Administer and monitor application servers and critical databases (SQL Server, Firebird, PostgreSQL), tuning queries and indexes to improve response times and keep services available.
  • Write the technical and architectural documentation, and provide advanced support and training that shortens issue resolution time for end users.

Systems Development Analyst

November 2021 — August 2025

  • Provided on-site and remote technical support to a network of public registry offices across four Brazilian states, resolving incidents that blocked day-to-day operations.
  • Owned SQL Server (2008+) and Firebird databases end to end: installation, initial configuration, access and security policies, and backup routines.
  • Ran proactive maintenance and performance monitoring on databases and servers, tuning queries and restructuring indexes to reduce response times.
  • Analysed production data and resolved complex software integration problems across systems, handling business-critical records.

Technical Skills

Grouped by where each technology is actually used, so the scope of experience is not over-read.

Backend & APIs

Go Python Delphi FastAPI Django Node.js REST APIs Layered / hexagonal architecture

Go, Python and Delphi are the languages I work in day to day; Bridopen, my open-source project, is also written in Go.

Databases & Data

SQL SQL Server PostgreSQL Firebird Relational data modelling Query & index tuning Stored procedures, triggers, views Transactions Backup & access control SSIS (ETL)

SSIS was used in coursework and ETL exercises, not yet in a production pipeline.

Engineering Tools

Git Docker & Docker Compose GitHub Actions (CI) Automated tests (go test, testify) Versioned SQL migrations Technical documentation

Web & Interfaces

HTML CSS Tailwind CSS TypeScript Server-side rendering (html/template)

About & Education

I hold a Bachelor's degree in Computer Engineering and am registered as an engineer in the Brazilian CONFEA/CREA system — the federal council that regulates the engineering professions in Brazil. It is a Brazilian registration; it is not equivalent to, and I do not present it as, a foreign PE licence.

My day-to-day work is building and maintaining systems used by public registry offices in Brazil: designing the relational model, implementing features in Go, Delphi and Python, integrating systems that were never designed to talk to each other, and keeping SQL Server, Firebird and PostgreSQL instances fast and backed up.

I also build web applications in Go, such as Bridopen — open source, with the architecture, the tests and the security decisions there to be read, run and challenged.

Architecture and performance

A large part of my work is making systems that already exist respond better: reading execution plans, rewriting queries, revisiting indexes and the data model, and automating critical routines that used to depend on manual steps — on databases in constant daily use.

On the development side, I structure applications in layers, with REST APIs and explicit boundaries between the domain, the services and persistence, so that performance, integration and reliability follow from the architecture rather than from one-off fixes. The aim is steady response times and systems that stay predictable as the data and the number of users grow.

Academic background

Bachelor's degree

Computer Engineering

Universidade de Cuiabá — Brazil

Professional registration

CONFEA/CREA system — Brazil

Registered engineer; practising as Computer Applications Engineer.

Postgraduate specializations

Brazilian lato sensu postgraduate programmes at Universidade Pitágoras Unopar Anhanguera. Software Engineering and Data Engineering are the two axes of my practice; the remaining programmes support them.

Software Engineering
Specialization axis
Engineering practice across the software lifecycle: architecture, design patterns, code quality, and building and consuming REST APIs with attention to versioning and documentation.
January 2026 — July 2026
Data Engineering
Specialization axis
Structuring, preparing and integrating large volumes of data so they can be analysed reliably — modelling, ingestion, data quality and processing.
December 2023 — June 2024
Database
Administration
Supporting programme
Administration of relational databases with a focus on security, integrity and availability, plus performance work on queries, indexes, procedures, triggers, transactions and views.
August 2023 — February 2024
Data Architecture
and Governance
Supporting programme
Policies and structures that keep data assets consistent: data quality, compliance, integration between systems, cataloguing and regulatory alignment.
June 2024 — December 2024
Systems Analysis
and Development
Supporting programme
From requirements to working software in Go and Delphi: programming logic, REST APIs, database integration, legacy maintenance, testing and versioning.
January 2025 — July 2025
Cloud Computing
Supporting programme
Cloud platforms and virtualisation: the main tools, data security, storage solutions, and planning and troubleshooting infrastructure across business contexts.
June 2025 — December 2025

Courses & certifications

Completed training, mostly around SQL Server, ETL and Azure data services. Items marked exam preparation are preparation courses — not the vendor certification itself.

Completed August 2024 · Udemy

SQL Server Integration Services (SSIS) — advanced ETL

Data integration, transformation and movement with SSIS: ETL processes, data warehouse staging and automated loads.

Read more

Completed July 2024 · Power Tuning

Day-to-day work of a SQL Server DBA

Administration, automation and performance in SQL Server, with a focus on access control and operational efficiency.

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Completed March 2024 · Power Tuning

50 tips and shortcuts — SQL Server Management Studio

Productivity and good practice in SSMS for everyday development and administration work.

Read more

Completed September 2024 · Power Tuning

Azure SQL Database

Fundamentals and operation of relational databases on Microsoft Azure, aligned with DBA and data engineering practice.

Read more

Completed · Ka Solution

Microsoft Azure AI Fundamentals (AI-900) — exam preparation

Eight-hour course delivered by Microsoft Certified Trainers, covering AI workloads, machine learning, computer vision and NLP on Azure.

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Completed June 2025 · Udemy

DP-300 Azure Database Administrator Associate — exam preparation

Preparation course for the DP-300 exam. This is course completion, not the Microsoft certification.

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Completed June 2025 · Udemy

SQL for data analysis — beginner to advanced

SQL queries and techniques applied to analysis and data-supported decision making.

Read more

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Contact

I am open to software engineering and data engineering roles, including international and remote positions. The fastest way to reach me is by email.

Email: engenheiroaraujo@outlook.com.br

Download Resume (PDF · English)