Learning Hub

Teal canonical blockchain with an amber orphan branch and a translucent explorer data panel.

Building a Reorg-Safe Blockchain Explorer in Java

A blockchain explorer must explain changing history. Build a Java indexing core that handles reorgs, preserves observations and protects finalized checkpoints.

By Enrico Homann, 1 month ago October 2, 2026

Concurrency

Java 27 Structured Concurrency: Cancellation Is Part of Your Architecture

Parallel reads are easy to start. Java 27 structured concurrency makes their lifetime explicit—but cancellation still depends on your adapters.

By Enrico Homann, 1 month ago October 2, 2026

Three parallel task paths inside one glass enclosure; two converge while an amber path is interrupted and awaits completion.

Glass service blocks linked by telemetry paths, with an inspection gate revealing traces and metric bars.

Best Practices

Your Telemetry Needs Tests: OpenTelemetry Contracts for Java

The payment provider fails. Your checkout counter keeps rising. The dashboard looks healthy. The trace contains a checkout span, but the payment call sits in another trace. And somewhere in the exception data, a customer email has slipped into your Read more

By Enrico Homann, 1 month ago October 1, 2026

Best Practices

Your Modular Monolith Needs an Architecture Test

A developer needs one more field for an order confirmation. The inventory module already has it, so they import a convenient internal class. The code compiles. The feature works. The boundary on the architecture diagram has just disappeared. That is Read more

By Enrico Homann, 1 month ago September 30, 2026

Three distinct architectural blocks connected through interfaces inside one transparent deployment boundary.

Typed AI decisions flow from a model signal through application policy to routing or human review.

Artificial Intelligence

Typed AI Decisions in Java: Make Uncertainty an Explicit Outcome

Research date: September 27, 2026. An architecture guide with an executable Java 21 example. A customer writes: “My payment failed, and now I cannot log in.” Should that ticket go to billing or technical support? A language model can suggest Read more

By Enrico Homann, 1 month ago September 28, 2026

Artificial Intelligence

Spring AI 2.1: Your RAG Pipeline Needs an Embedding Contract

Engineering analysis — September 27, 2026. Based on the Spring AI milestone released September 25. An enterprise search application can accept every vector, return plausible results, and still be wrong. The dangerous case is not necessarily a malformed request. It Read more

By Enrico Homann, 1 month ago September 27, 2026

An embedding producer passes tenant, space and dimension checks before a versioned index; its query encoder uses the same contract.

Abstract enterprise AI architecture routing work through a policy gateway to three model tiers and an evaluation loop.

Artificial Intelligence

GPT-6 Sol and Luna: Model Routing Is Now an Architecture Decision

GPT-6 Sol and Luna shift the question from which model is best to which model is justified for each task. Build a policy-driven router in tested Java.

By Enrico Homann, 1 month ago September 24, 2026

Artificial Intelligence

Verifiable AI Agent Commerce: ERC-8004, x402 and the Missing Trust Layer

AI agents can now discover services and pay onchain. Learn what ERC-8004 and x402 solve, where trust still fails, and build a tested tamper-evident interaction receipt.

By Enrico Homann, 1 month ago September 23, 2026