adam bien's blog

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SBCE is live at sbce.space (you say "space"). It is spec-driven development loop built on bce.design: the spec lives in your code, not in a markdown folder beside it.

Usually spec tools maintain the spec / Markdown files in a separate source tree. SBCE keeps it in the boundary package's own doc:

/// # Checkout
/// > Accept a cart and turn it into a confirmed, cancellable order.
///
/// ## Boundary
/// - `place-order`  — submit a cart for fulfilment
/// - `cancel-order` — withdraw an unfulfilled order
///
/// ## Requirements
/// ### R1: Place an order
/// - R1.1 — When a cart with at least one item is submitted, the BC shall create and confirm an order.
/// - R1.2 — If the cart is empty, then the BC shall reject the request.
package airhacks.checkout;

JEP 467 Markdown in /// comments. The same file is the source of truth and the published Javadoc. The BC name is the only identity: no frontmatter, no second file to sync.

Two modes. new writes the spec. apply converges the code until your stack's tests pass. "Done" is a green test run, not a checkbox.

No CLI, no dependencies, no installation. SBCE is a skill your agent reads, built on bce.design for the architecture and your stack skill for the code and tests.

ships with: airails.dev.

Subscribe to airhacks.fm podcast via: spotify| iTunes

Subscribe to airhacks.fm podcast via: spotify| iTunes

"Reflection and annotations: less needed at runtime as infrastructure becomes less dynamic, but annotations still valuable for type-safe metadata that LLMs can consume, AI token maxing and code quality: degraded LLM performance on chaotic codebases versus well-structured J2EE applications, building a career in Java with focus on continuous improvement and transferable fundamentals across languages, LightMetal: a thin Java 25 wrapper around llama.cpp using FFM bindings to run models locally with zero external dependencies and GPU-based inference, the ZSmith agent: an agentic stack with local models, BCE architecture, virtual-thread sub-agents, and a sandboxed file system implemented as Java tools, agent sandboxing via tiny Java tools with allow/deny/confirm permissions, AI Rails refactoring: extracting shared Java conventions into a reusable skill consumed by Java CLI, MicroProfile server, and BCE skills, standards and inference cost: Jakarta EE and MicroProfile are version-stable and well-known to LLMs, reducing token usage by an estimated 30-80 percent, API/SPI separation prevents hallucinations during code generation, a live demo generating a MicroProfile/Jakarta EE business component with Cloud Code, system tests, and a continuous testing loop, web frontends with web components and CSS instead of Angular or React, revisiting episode 47 from eight years prior: SSH database authentication, JSF, WAR modularization, identity preservation, JDBC revival, long-running transactions, and parallels to AI agents, workflow engines and agents: XState and AWS Step Functions specs as lightweight state-machine approaches"

GPU LLM inference on Apple Silicon, packaged as one Java 25 executable JAR, zero dependencies. lightmetal binds a Metal-enabled libllama.dylib through the Foreign Function & Memory API and runs Mistral- and Gemma-architecture GGUF models locally.

Build it with zb, point it at a GGUF, prompt it:

zb build
java --enable-native-access=ALL-UNNAMED -jar zbo/lightmetal.jar \
     -model ~/models/Mistral-Medium-3.5-128B-UD-Q5_K_XL-00001-of-00003.gguf \
     -prompt "What is Java?"

Add -serve and the same JAR exposes an Anthropic-compatible POST /v1/messages and an OpenAI-compatible POST /v1/chat/completions. xisting clients (zsmith, vibe) only need a base URL switch — the loaded GGUF wins, the model field is accepted and ignored.

Embedding into another Java app needs no compile-time dependency. lightmetal.jar registers a BinaryOperator via META-INF/services:

var generator = ServiceLoader.load(BinaryOperator.class).iterator().next();
var response  = generator.apply("/path/to/model.gguf", "What is Java?");

Just Java 25, llama.cpp, FFM, Metal — and a GGUF on disk.

1. In the Java 25 / JUnit 5 era, is reflection obsolete, or only for designing libraries/APIs rather than your own code? (Simon Richter)
2. Should I continue building my career in Java, or move toward AI given the current market and MNC layoffs? (Fanib)
3. jfrdoc on zSmith (Rıdvan)
4. airails.dev refactoring (java-conventions)
5. Time machine: 100 episodes back (47th episode):

   Database Authentication: SSH vs. username / password, Microservices with JSF frontend, How to modularize WARs, Dealing with denormalized databases, Java EE authentication (Active Directory), Identity preservation and audits in DB, JAX-RS authentication and principal delegation to EJB / CDI, Development in intranet environment, Reducing coupling between JavaScript components, Developers and operations -- their roles in the future, DeltaSpike project review, Impact of 3rd party libraries on build performance, Unpredictable, long running transactions, Propagating principals from JAX-RS to EJBs, Why it is a bad idea to resend a password on each request?, Dealing with security in credit card processing

Any questions left? Ask now: gist.github.com/AdamBien/33ece0569d45516d95163859aaaf8e1d and get the answers at the next airhacks.tv. Some questions are also answered with a short video: 60 seconds or less with Java

Ask questions during the show via twitter mentioning me: https://twitter.com/AdamBien (@AdamBien),using the hashtag: #airhacks or built-in chat at: airhacks.tv. You can join the Q&A session live each first Monday of month, 8 P.M at airhacks.tv

1. Devoxx Poland 2026: Token-Efficient, Well-Crafted Java #livecoding
   conference talk Devoxx Poland 2026 Krakow, Poland 18 June 2026
   https://devoxx.pl/talk?id=15451
2. VibeKode Conference: How To Write Great Code with LLMs #vibeless
   conference talk VibeKode Conference Munich, Germany 24 June 2026
   https://vibekode.it/speaker/adam-bien/
3. Spec-Driven Java Development at LLM Speed[online event]
   online workshop 2 July 2026
   https://workshops.adam-bien.com
4. LLM-Assisted Web Components: No Frameworks, No Dependencies. Just Web Standards[online event]
   online workshop 16 July 2026
   https://workshops.adam-bien.com
5. Entwickler Summit 2026: Fewer Tokens, Better Apps: With Standards and Java
   conference talk Entwickler Summit 2026 Berlin, Germany 17 September 2026
   https://entwickler.de/entwickler-summit/
6. airhacks.tv Questions and Answers #livestream[online event]
   live streaming show first monday of the month, 8pm CET
   https://www.meetup.com/airhacks/

The in-person edition of airhacks is back at MUC Airport: "Architect-Grade Java with LLMs" airhacks.university

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Java projects are still plagued by outdated habits: excessive layers, unnecessary abstractions, more YAML/XML than code, tests for obvious things like getters, "Stats and Ticket-d riven Development" and systems where everything is configurable but nothing varies, leaving business logic buried under unnecessary complexity. It’s time to focus on code again. This session will demonstrate how modern Java 25 and standards can help us to reduce unnecessary complexity. The focus is on shipping real business logic with greater simplicity and maintainability.

Two Time Machines: Revisiting the 45th Episode After 9 Years, Java 25 Scripting With Zero Dependencies, Java vs. Kotlin in 2025, Web Components and Standards Without Frameworks, Multiple Datasources With Different Permissions for AI Agents, Connection Pools and JPA Cache in Serverless Environments, Why XA Transactions Are a Bad Idea, JavaFX Revival With Official Oracle Support, EJBs vs. CDI Pooling and Jakarta EE 12 Native Pooling Plans, BCE Design and AI Rails for AI Agents, Jakarta Data and Delta Spike Evolution, Docker Swarm vs. Kubernetes vs. OpenShift for Java Developers, Server Push With WebSockets and SSE in the MCP Era, Role-Based Access With MicroProfile JWT and @RolesAllowed, Scala vs. Rust vs. Java 25 Analysis, Why LLMs Understand Java Better Than Other Languages, zsmith Agent Harness in Pure Java 25, LangChain4j With Quarkus and Native Compilation, Zero-Dependency JUnit Runner Under 1 Second, JAX Frankfurt, AirHacks Munich Airport Workshop December 2026, Summer AirHacks Online, JCon Cologne, Devoxx Greece, JavaOne, Devoxx London, Geekon Krakow

Subscribe to airhacks.fm podcast via: spotify| iTunes

1. Opinion about the Rust programming language (asked by @Pscheidl on LinkedIn)
2. Time machine: the 46th airhacks.tv from January 2018

   Application metrics and monitoring in Java EE, ServerSockets vs higher-level alternatives, SSE, WebSockets, DAO anti-patterns, JPA historisation, SLSB tuning, Docker, Kubernetes, OpenShift and more

3. Time machine: the 45th airhacks.tv from December 2017

   Kotlin in Java EE, JasperReport alternatives, custom REST headers, two persistence units in CDI, JPA internals, JWT authentication, Web Components, offline-first PWAs and more

4. airhacks workshops return to Munich Airport
5. conference report

Any questions left? Ask now: gist.github.com/AdamBien/4c2a1c099321bac29ecb6ebc262ae196 and get the answers at the next airhacks.tv. Some questions are also answered with a short video: 60 seconds or less with Java

LLMs know Java's normative APIs, specifications, and implementations. That changes how you write code. Code structure, naming conventions, and adherence to standards directly affect what LLMs generate. Well-structured, zero-dependency Java produces more consistent, more predictable LLM output and scales to big projects. Starting from a blank project, each step demonstrates how code organization, standard API usage, and consistent patterns influence LLM-assisted development. The same principles that make code readable for developers also make it processable for LLMs. No slides. No theory. Just code. Questions welcome at any time.

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Java 25 source-file mode turns a single file into an executable command. No compilation, no build tool, no .java extension. Here is how to create a zhello script:

1. Create a file named zhello (no extension) with the shebang #!/usr/bin/env -S java --source 25
2. Add an instance void main() method that calls IO.println("hello, world")
3. Make it executable: chmod +x zhello
4. Install it system-wide: sudo cp zhello /usr/local/bin/

The entire script:

#!/usr/bin/env -S java --source 25

void main() {
    IO.println("hello, world");
}

BCE pattern from 1992: top-level packages named by context not by layer, at most 3 sub-packages: Boundary, Control, Entity, @Transactional belongs only on the Boundary — one button push equals one use case equals one transaction, Hibernate Validator skipped in favor of custom Control-layer validation for precise 400-error handling, zero-dependency MCP server by Mr. Aldo from France: built with BCE and zero-dependency principles, Agent Smith live demo: zero-dependency Java 25 agent framework in ~130KB single JAR, transcriber agent with episodic memory and agent delegation, GPU Llama / TornadoVM: Apple Metal support for running Mistral and DevStral locally, plans to run Agent Smith without cloud, Z ecosystem: ZDate, ZJDocFind, ZUnit single-file test runner in ~300 lines with parallel execution, ZB build tool — all zero-dependency Java 25 scripts, LLMs understand standards better than frameworks — enables lean code generation without external dependencies, Enterprise Fire April 1st skill: converting Hello World to 73 classes with all patterns, hexagonal architecture appears for the first time on AirHacks, upcoming AirHacks Live summer workshops on spec-driven Java development and front-ends without dependencies

Do you have any more questions? See you at: airhacks.live

Subscribe to airhacks.fm podcast via: spotify| iTunes| YouTube

Topics for the 145th airhacks.tv:

1. airails.dev microprofile-server skill: @Transactional in the boundary vs. control layer for bulk processing and synchronous API calls
2. BCE architecture in Jakarta Faces applications - how to structure them
3. Local inference with Tornado / Java GPULLama3
4. airails.dev microprofile-server skill: why never use quarkus-hibernate-validator? Alternatives to manual validation
5. MCP server with Zero-framework / BCE architecture by Aldo Lushklja: zdtp-mcp, blog post
6. Agent zSmith news
7. zeeds (Java Zero-Dependency Seed Scripts) news

See you every first Monday of the month at https://airhacks.tv 8pm CET (UTC+1:00). Show is also announced at: meetup.com/airhacks.

Ask questions during the show via twitter mentioning me: https://twitter.com/AdamBien (@AdamBien),using the hashtag: #airhacks or built-in chat at: airhacks.tv. You can join the Q&A session live each first Monday of month, 8 P.M at airhacks.tv

1. JCON Europe 2026: Livecoding: Creating Beautiful Java Code With LLM and Agents
   conference talk JCON Europe 2026 Cologne, Germany 21 April 2026
   https://schedule.jcon.one/2026/speakers
2. Devoxx Greece 2026: Your Java Code Is Your LLM Prompt
   conference talk Devoxx Greece 2026 Athens, Greece 23 April 2026
   https://m.devoxx.com/events/dvgr26/talks/13551/session-by-adam-bien
3. JAX, Mainz: Business Logic First: Escaping Java's Bloat Addiction
   conference talk JAX, Mainz Berlin, Germany 5 May 2026
   https://jax.de/serverside-enterprise-java/business-logic-first-java/
4. JAX, Mainz: Live Coding Production Java: Incremental Development with LLMs
   conference talk JAX, Mainz Berlin, Germany 5 May 2026
   https://jax.de/big-data-machine-learning/java-incremental-development-llm-java/
5. Geecon: The 50x Developer: Java's Unfair Advantage in the Age of AI Agents
   conference talk Geecon Krakow, Poland 14th May 2026
   https://2026.geecon.org/speakers/info.html?id=1062
6. VibeKode Conference: How To Write Great Code with LLMs #vibeless
   conference talk VibeKode Conference Munich, Germany 24 June 2026
   https://vibekode.it
7. Spec-Driven Java Development at LLM Speed[online event]
   online workshop 2 July 2026
   https://workshops.adam-bien.com
8. LLM-Assisted Web Components: No Frameworks, No Dependencies. Just Web Standards[online event]
   online workshop 16 July 2026
   https://workshops.adam-bien.com
9. airhacks.tv Questions and Answers #livestream[online event]
   live streaming show first monday of the month, 8pm CET
   https://www.meetup.com/airhacks/

Subscribe to airhacks.fm podcast via: spotify| iTunes|