João Ielen

Software Engineer focused on
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Hello

Software Engineer based in Brazil with professional experience in backend and full-stack development, automation, APIs, databases, data pipelines, monitoring, and production systems. View my résumé.

I hold a bachelor's degree in Software Engineering and have two years of experience at Pilgrims Consulting, where I currently work as a Mid-level Software Developer. My work spans software development, automation, databases, infrastructure, observability, and production environments. Explore my tools.

I am fluent in English, speak native Portuguese, and have Japanese at approximately JLPT N4 level. I am open to software engineering, backend, automation, QA, DevOps, infrastructure, data, and related technology roles.

João Ielen

Professional Experience and Education

02

Previous academic studies

Studies in Physics and Computer Science

Universidade Federal do Paraná

Completed several semesters in Physics and in the Bachelor's Degree in Computer Science, developing foundations in mathematics, scientific reasoning, algorithms, and computing.

  • Physics
  • Computer Science
  • Mathematics
  • Algorithms
03

2021 – 2026

Bachelor's Degree in Software Engineering

UniOpet

Completed a bachelor's degree focused on software architecture, systems development, databases, data engineering, and the software development lifecycle.

  • Software Engineering
  • Databases
  • Data Engineering
04

2023 · Six-month program

Python and Data Analysis Tutor

UniOpet · Elas no STEM

Taught and mentored students throughout a six-month Python and data analysis program, providing guidance on programming concepts, debugging, and practical data workflows.

  • Python
  • Data Analysis
  • Teaching
  • Mentoring
05

Dec 2023 – Jun 2024

Systems Development Intern

Vital Scheffer

Automated routines with Python, maintained WordPress applications and databases, updated Metabase dashboards, supported users, handled internal requests, and helped plan new tools.

  • Python
  • WordPress
  • SQL
  • Metabase
  • User Support
06

Jun 2024 – Dec 2024

Systems Development Intern

Pilgrims Consulting

Developed Django REST and Angular features, Selenium automations, process bots, API integrations, Excel reports, Metabase dashboards, and distributed database routines.

  • Django REST
  • Angular
  • Selenium
  • APIs
  • Metabase
07

Dec 2024 – 2025

Junior Systems Developer

Pilgrims Consulting

Built and optimized systems with C#, TypeScript, and Python; maintained Django REST and Angular applications; and worked with Airflow, dbt, PostgreSQL, Docker, AWS, and ERP integrations.

  • C#
  • TypeScript
  • Python
  • Airflow
  • PostgreSQL
  • Docker
08

2025 – Present

Mid-level Systems Developer

Pilgrims Consulting · 2 years at the company · Curitiba, Brazil

Develop and maintain backend and full-stack solutions, APIs, internal platforms, automations, database workflows, observability platforms, and production infrastructure.

  • Python
  • TypeScript
  • REST APIs
  • SQL
  • Docker
  • Linux

Key Achievements

Selected outcomes from my current role, focused on reliability, visibility, and operational improvement.

01

Observability platform from implementation to operation

Built and maintain an observability platform covering approximately 95 targets across more than 30 machines for 8 clients. Migrated 7.9 GB of historical metrics and 18 dashboards without data loss, created reusable dashboards, and developed custom Python exporters.

Prometheus · Grafana · Alertmanager · Zabbix · Checkmk · Python

02

Database reliability and performance

Led the recovery and cutover of a 40 GB MariaDB production cluster with 58 databases and about 2,000 tables. Audited 1,983 tables, recovered 419 business records, corrected replication monitoring, and tuned PostgreSQL workloads.

MariaDB · PostgreSQL · GTID Replication · SQL · Performance Tuning · RCA

03

Infrastructure, networks, and operational automation

Standardized provisioning with Ansible, managed a Tailscale network with more than 30 devices, published internal services with Traefik and TLS, and optimized cAdvisor collection from 185% to 2% CPU usage.

Ansible · Tailscale · Traefik · Docker Compose · Linux · cAdvisor

Selected Projects

A few systems I designed and delivered as part of a broader professional role.

PROJECT 01

Omnichannel GLPI Service Desk Bot

Pilgrims Consulting

Service desk bot integrated with Microsoft Teams and WhatsApp, featuring live GLPI forms, native approvals, proactive status notifications, technician alerts, and image attachments.

Python · GLPI API · Azure Bot Framework · Adaptive Cards

PROJECT 02

Grafana Observability

Pilgrims Consulting

Created unified dashboards using Prometheus, cAdvisor and blackbox to diagnose and correct performance issues and bring up to 95% availability to applications.

Blackbox · cAdvisor · Grafana · Prometheus

PROJECT 03

Airflow Datalake Construction

Pilgrims Consulting

Designed and implemented end-to-end analytics solutions across multiple client projects, orchestrating ETL/ELT pipelines with Apache Airflow and delivering client-facing dashboards in Metabase.

Apache Airflow · SQL · Data pipelines · Data Science

PROJECT 04

Living Infrastructure Documentation

Pilgrims Consulting

Automation that reads network topology in real time and publishes an interactive SVG diagram to the internal wiki on a scheduled workflow.

Python · SVG · Cron · Wiki.js · Network Automation

© 2026 João Ielen.