Posts

A slip-box of notes wired into an AI agent

Using Zettelkasten with Agents

How structured note-taking with Zettelkasten became the memory layer for my AI agents, and how it saves me tokens, time and money.

One trace threading through five lanes, from browser to Angular, Java, .NET, Go and Node, over HTTP, gRPC and Kafka

Observability in Practice: Distributed Systems, Cost and Production

Part 2 of 2. One browser click crossing five systems and four languages in a single trace, and what changes when that goes to production: tail sampling, cardinality, exemplars and SLOs.

Trace waterfall of a single request: one fast root span above a descending ladder of forty identical SELECT queries

Observability in Practice: Why Instrument, and How Quarkus Makes It Cheap

Part 1 of 2. Why observability became the market standard after OpenTelemetry graduated from the CNCF, the minimum vocabulary to follow along, and what Quarkus gives you without writing a line of code.

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.