Welcome to my blog! 👋

I help professional Java developers master the ‘Quarkus Way’, empowering them to build high-performing apps and become highly valued engineers. Soli Deo Gloria!

Kafka Integration in Quarkus: Reactive Messaging, @Incoming and @Outgoing

Take messaging outside the application with SmallRye Reactive Messaging. Channels vs Topics, @Incoming, @Outgoing, Emitter, automatic JSON serialization, and Dev Services starting the broker without you installing anything.

Matheus Oliveira on the main stage at TDC Floripa 2026

Face to Face with Claude: I Got Pulled Onto the TDC Main Stage With No Warning

I almost didn’t go. The panel topic changed, my speaking partner couldn’t make it, and I hadn’t budgeted for the trip. Hours after arriving, the founder of the largest tech conference in Latin America called me onto the main stage in front of 200+ people. This is the interview where I explain how.

Minimalist diagram showing four interconnected pillars labeled Style, Characteristics, Components, and Decisions, on a dark background

Software Architecture Fundamentals: the 3 laws and 8 expectations every developer should know

Everything in software architecture is a trade-off. A deep dive into Chapter 1 of Fundamentals of Software Architecture: the 3 laws that govern every architectural decision and the 8 expectations of an architect.

Minimalist diagram showing a central 'Agent' node connected to four modules: Soul, Memory, Skills and Tools, on a dark purple background

Qlawkus: Build Personal AI Agents in Java with Quarkus

Introducing Qlawkus, a set of Quarkus extensions for building personal AI agents in Java: memory that’s automatically injected, procedural skills, voice-enabled messaging, and composition via agent.yml.

A 16-bit SNES pixel art illustration of a community hub where characters catch bugs in jars, write on scrolls, discuss around a fountain, and donate gold coins.

How to Contribute to Open Source Without Writing Code

Think contributing to Open Source is just about opening PRs? Discover how to help the community through issues, discussions, articles, and donations, even without focusing on code.

Pixel art SNES 16-bit of a retro dispatch center with a robot operator routing glowing message packages through neon rails to three distinct receiver nodes, neon SIGNALS sign above

Internal Messaging in Quarkus: Signals, @Receives, and the New Publisher-Subscriber Pattern

Decouple components with Quarkus Signals. Type-safe resolution, @Receives, pub/sub vs unicast vs request-reply, and why Spring has no native equivalent.

SNES 16-bit pixel art of a retro dispatch center with a robot operator routing glowing message packets down neon rails toward three distinct receiver nodes, neon EVENT BUS sign overhead

Internal Messaging in Quarkus: Event Bus, ConsumeEvent, and the Publisher-Subscriber Pattern

Decouple components with the Vert.x Event Bus. Pub/Sub vs Point-to-Point, asynchronous consumers with @ConsumeEvent, and why Spring has no native equivalent.

NES-style pixel art: a retro game console with several cartridges floating above its slot, each cartridge labeled like a plugin (NROM, MMC1, MMC3), a glowing 'ServiceLoader' label on the console reading them automatically

Java SPI: The Built-in Superpower Every Developer Should Know

There is a plugin system hiding inside the JDK that most developers never use on purpose. Java SPI (ServiceLoader) lets you add behavior without touching the code that consumes it. I show it with real code from my NES emulator, kill the fragile META-INF file with Google AutoService, cover the modern JPMS variant, and finish with how Quarkus does the same idea at build time.

OCI Notifications and Event-Driven Architecture

Event-Driven on the Free Tier: OCI Notifications (ONS) as an Event Bus

Discover how to implement Event-Driven Architecture on OCI Always Free using OCI Notifications (ONS). ONS delivers 1M HTTPS notifications/month and 1000 emails/month for free.

SNES 16-bit pixel art sky with a fluffy popcorn cloud (floccus) raining AWS service icons (S3, DynamoDB, Lambda) onto a pixel laptop, neon FLOCI sign above

Floci: a Free, Drop-in LocalStack Alternative Built on Quarkus

LocalStack Community froze in March 2026 and now asks for an auth token. Floci is the no-strings-attached replacement: a free, MIT-licensed, Quarkus-native local AWS emulator. I test it for real: AWS CLI, a real Lambda, two ways of wiring a Quarkus app (Dev Services and Testcontainers), and a LocalStack migration.