Open to opportunities

Alex Oliveira

@alexoliveira

Message

Backend-focused software engineer specializing in Ruby on Rails and Java, building business-close enterprise systems.

Portugal

Message

What I'm looking for

I’m looking to deepen my work within the Java ecosystem and enterprise systems—designing reliable backend architectures, optimizing data pipelines and observability, and partnering with teams to ship high-impact products.

I’m a software engineer with over 10 years of experience in backend development and systems architecture, specialized in Ruby on Rails and Java. I’ve made high-impact technical decisions, led teams, and built products from scratch—staying close to the business while delivering reliable, production-ready systems.

Most recently at DataSmart, I contributed to a real-time water monitoring analytical platform by optimizing PostgreSQL queries, improving Apache NiFi ETL reliability, and using TimescaleDB continuous aggregations to reduce load. Previously at Flecto, I defined frontend technical architecture, supported multiple applications, and helped integrate services with OpenAI, Cloudflare Workers, and AWS Lambda—while strengthening observability with Elastic Stack and test/CI discipline, plus a strong, practical approach to AI usage.

Experience

Work history, roles, and key accomplishments

Current

Backend Developer

Current

DataSmart Lda

Jul 2025 - Present (1 year)

Built and maintained backend platform features for a real-time water monitoring product, supporting production operations and ongoing evolution. Optimised PostgreSQL/TimescaleDB queries and ETL pipelines, and implemented observability, CI/CD, and onboarding automation.

Ruby on Rails PostgreSQL SQL Apache NiFi Apache Kafka TimeScaleDB Elasticsearch Logstash Kibana Azure DevOps RSpec N+1 Query Detection CI CD Codex Claude Code

Current

Founding Engineer

Current

REM Advisor

Jul 2025 - Present (1 year)

Helped build the MVP for a real estate lead capture and CRM platform, defining and deploying core technical architecture. Supported MVP delivery and beta user onboarding while setting up infrastructure and delivery processes.

Spring Boot Java PostgreSQL Auth0 CDN Vercel Heroku Azul OpenJDK Logstash Cloudflare Tunnel Docker Swarm Portainer Nginx Infrastructure Deployment

Back End Developer

Flecto

May 2022 - Jul 2025 (3 years 2 months)

Led technical architecture and team alignment across multiple applications, delivering backend features in Ruby on Rails. Implemented performance and observability improvements and built integrations including OpenAI and AWS serverless components.

Ruby on Rails OpenAI Cloudflare Workers AWS Lambda PostgreSQL Sentry Logstash OpenSearch Sidekiq Apidog Swagger Heroku Vercel

Full Stack Developer

NEX T Engineering

Apr 2021 - May 2022 (1 year 1 month)

Modernised internal financial management systems by migrating from Java Swing to a web platform. Developed the React and Spring Boot implementation and produced performance reports for the central team.

React Spring Boot Redux Web Performance

Senior Frontend Developer

Conexa Saúde

Jul 2020 - Jun 2021 (11 months)

Contributed to a digital health backoffice for clinic and physician management, including ongoing migration and maintenance of core UI systems. Structured a design system, migrated toward React/Next.js, maintained legacy medical records UI, and supported GDPR compliance interfaces.

Vue.Js JSP React Next.js Storybook jQuery GDPR Compliance Design Systems

Full Stack Developer

DealerUp Consultoria e Sistemas

Jul 2019 - Jul 2020 (1 year)

Developed and maintained a dealership management platform using Vue.js and Laravel. Proposed and built an offline Flutter mobile application for presenting tractor stock inventory without network coverage.

Vue.Js Laravel Flutter

Full Stack Developer

Studio Prime

Feb 2017 - Sep 2019 (2 years 7 months)

Worked on an audiovisual media management and logistics platform, building features using PHP and jQuery. Developed a Flutter warehouse scanning/check-out experience and supported web label printing and CSV-based data import operations.

PHP jQuery Flutter Warehouse Scanning Label Printing ORM

Developer

Agência H1 Code

Mar 2014 - Jan 2017 (2 years 10 months)

Provided early-career development work including templates/plugins and tooling for Ragnarok Online server infrastructure. Built a PHP+SSH platform for compiling/managing C++ servers and implemented NPC scripting using Gravity’s engine.

PHP SSH C++Ragnarok Online Gravity Engine Templates