Personal site of Dan Vega https://www.danvega.dev en-us Wed, 30 Sep 2026 00:48:23 GMT danvega@gmail.com (Dan Vega) danvega@gmail.com (Dan Vega) A hands-on Spring Boot 3 to 4 migration: upgrade a real app, then fix Jackson 3, modular starters, the missing H2 console, test imports, and JSpecify. https://www.danvega.dev/blog/spring-boot-3-to-4-migration https://www.danvega.dev/blog/spring-boot-3-to-4-migration Thu, 24 Sep 2026 09:00:00 GMT Dan Vega Spring Boot Java Jackson Spec-driven development without the team process. The lightweight plan I use as a solo developer, from one PRODUCT.md to a retro, on a Spring Boot Stripe store. https://www.danvega.dev/blog/spec-driven-development-solo-developers https://www.danvega.dev/blog/spec-driven-development-solo-developers Wed, 23 Sep 2026 09:00:00 GMT Dan Vega Spring Boot AI Java Learn Spring AI TypeSafe by building a model router from an empty app. One Choice question to Jev picks the cheapest OpenAI model tier for every prompt. https://www.danvega.dev/blog/spring-ai-typesafe-model-router https://www.danvega.dev/blog/spring-ai-typesafe-model-router Tue, 22 Sep 2026 09:00:00 GMT Dan Vega Spring AI Spring Boot Java Use the Jev Spring Boot Starter to call TypeSafe's Jev API with one dependency and an injected JevClient, then see how Spring Boot 4 auto-configuration works. https://www.danvega.dev/blog/jev-spring-boot-starter https://www.danvega.dev/blog/jev-spring-boot-starter Mon, 21 Sep 2026 09:00:00 GMT Dan Vega Spring Boot Java Jev Use Claude Code skills for podcast automation: edit audio, create show notes, prepare a Transistor upload, and open a spring.io PR after the episode is live. https://www.danvega.dev/blog/claude-code-skills-not-just-for-coding https://www.danvega.dev/blog/claude-code-skills-not-just-for-coding Sun, 20 Sep 2026 09:00:00 GMT Dan Vega AI Software Development Learn Java structured concurrency in JDK 27 with a runnable example comparing sequential calls, virtual threads, and StructuredTaskScope failure handling. https://www.danvega.dev/blog/java-structured-concurrency-jdk-27 https://www.danvega.dev/blog/java-structured-concurrency-jdk-27 Sat, 19 Sep 2026 09:00:00 GMT Dan Vega Java Call TypeSafe Jev from Java and Spring Boot with RestClient. Build a complete support-ticket example with typed questions, Java records, and a mocked API test. https://www.danvega.dev/blog/getting-started-jev-java-spring-boot https://www.danvega.dev/blog/getting-started-jev-java-spring-boot Fri, 18 Sep 2026 09:00:00 GMT Dan Vega Spring Boot Java AI How I built Content OS with Claude Code and Spring Boot to manage videos, blog posts, and newsletters, and what changes when you build software for one user. https://www.danvega.dev/blog/content-os-claude-code-spring-boot https://www.danvega.dev/blog/content-os-claude-code-spring-boot Thu, 17 Sep 2026 09:00:00 GMT Dan Vega Spring Boot Spring AI Java AI Render real ColdFusion .cfm templates inside a Spring Boot app using the BoxLang Spring Boot starter and one undocumented boxlang.suffix property. https://www.danvega.dev/blog/coldfusion-inside-spring-boot-boxlang-starter https://www.danvega.dev/blog/coldfusion-inside-spring-boot-boxlang-starter Tue, 15 Sep 2026 09:00:00 GMT Dan Vega Spring Boot Java BoxLang Learn the 5 steps of AI adoption mapped out by Boris Cherny, creator of Claude Code, and how to move from copy-pasting code to supervised autonomy. https://www.danvega.dev/blog/five-steps-of-ai-adoption https://www.danvega.dev/blog/five-steps-of-ai-adoption Wed, 05 Aug 2026 09:00:00 GMT Dan Vega AI Spring Boot Java Can you trust AI-generated code? It depends on what you already know. A look at why AI code feels great in unfamiliar stacks and how to verify it. https://www.danvega.dev/blog/can-you-trust-ai-generated-code https://www.danvega.dev/blog/can-you-trust-ai-generated-code Fri, 31 Jul 2026 09:00:00 GMT Dan Vega Spring Boot Java AI Learn a practical workflow for upgrading dependencies with AI, using scope, scale, and stakes to decide when to reach for an LLM to patch your projects. https://www.danvega.dev/blog/upgrading-dependencies-with-ai https://www.danvega.dev/blog/upgrading-dependencies-with-ai Thu, 30 Jul 2026 09:00:00 GMT Dan Vega AI Web Development Nuxt Learn how to build Spring AI guardrails with SafeGuardAdvisor, custom PII masking, and output rails to stop prompt injection and data leaks. https://www.danvega.dev/blog/spring-ai-guardrails-safeguard-advisor https://www.danvega.dev/blog/spring-ai-guardrails-safeguard-advisor Tue, 28 Jul 2026 09:00:00 GMT Dan Vega Spring AI Spring Boot Java Learn what that docker-compose.yml in every Java repo actually does. Spin up Postgres with one command and run any project you clone with zero setup. https://www.danvega.dev/blog/docker-compose-for-java-developers https://www.danvega.dev/blog/docker-compose-for-java-developers Mon, 27 Jul 2026 09:00:00 GMT Dan Vega Java Docker Postgres Build a Claude-style 'Calling tool...' UI with Spring AI 2.0's ToolCallingAdvisor. Stream live tool call events over SSE from the ChatClient advisor chain. https://www.danvega.dev/blog/spring-ai-tool-calling-advisor-2-0 https://www.danvega.dev/blog/spring-ai-tool-calling-advisor-2-0 Fri, 24 Jul 2026 09:00:00 GMT Dan Vega Spring AI Spring Boot Java Embabel 1.0 is GA. What Rod Johnson's AI agent framework for the JVM means for Java developers, what changed on the road to 1.0, and how to get started. https://www.danvega.dev/blog/embabel-1-0-ga https://www.danvega.dev/blog/embabel-1-0-ga Mon, 20 Jul 2026 09:00:00 GMT Dan Vega java spring-ai embabel ai-agents My complete 10-stage content creation workflow for YouTube: ideation, packaging, AI rough cuts, repurposing videos into blog posts, Shorts, and a newsletter. https://www.danvega.dev/blog/content-creation-workflow https://www.danvega.dev/blog/content-creation-workflow Sat, 18 Jul 2026 09:00:00 GMT Dan Vega YouTube Blogging AI Learn how Spring AI 2.0 validates LLM JSON against your schema and automatically retries failures with self-correcting structured output. A beginner guide. https://www.danvega.dev/blog/self-correcting-structured-output https://www.danvega.dev/blog/self-correcting-structured-output Fri, 17 Jul 2026 09:00:00 GMT Dan Vega Spring AI Spring Boot Java Can you use Java for AI? Yes. For building real AI applications it might be the better choice. Why the JVM, Spring AI, and your existing team are enough. https://www.danvega.dev/blog/can-you-use-java-for-ai https://www.danvega.dev/blog/can-you-use-java-for-ai Wed, 15 Jul 2026 09:00:00 GMT Dan Vega Java AI Spring AI Spring Boot 3.5 reached end of life in June 2026 and every 3.x branch is now unsupported. What that means, and how to plan your Spring Boot 4 upgrade. https://www.danvega.dev/blog/spring-boot-end-of-life https://www.danvega.dev/blog/spring-boot-end-of-life Tue, 14 Jul 2026 13:00:00 GMT Dan Vega Spring Boot Java Spring Boot 4 AI Port 8080 already in use? Learn how to find and kill the process running on a port on Windows, macOS, and Linux—with copy-paste commands for each. https://www.danvega.dev/blog/kill-process-on-port https://www.danvega.dev/blog/kill-process-on-port Tue, 14 Jul 2026 09:00:00 GMT Dan Vega Java Spring Boot Spring AI 2.0's tool search brings dynamic tool discovery to Spring Boot—load tools on demand instead of into every request to cut token usage and cost. https://www.danvega.dev/blog/spring-ai-tool-search https://www.danvega.dev/blog/spring-ai-tool-search Thu, 09 Jul 2026 09:00:00 GMT Dan Vega Spring AI Spring Boot Learn to build custom Spring AI advisors with the BaseAdvisor interface to log available tools, track tool invocations, and count token usage on every LLM call. https://www.danvega.dev/blog/spring-ai-custom-advisors-tool-logging-token-counter https://www.danvega.dev/blog/spring-ai-custom-advisors-tool-logging-token-counter Wed, 08 Jul 2026 09:00:00 GMT Dan Vega Spring AI Spring Boot Java UI.sh is a collection of agent skills from the Tailwind CSS and Refactoring UI team that give Claude Code and Codex the polish of a senior UI designer. https://www.danvega.dev/blog/ui-dot-sh-agent-skills-for-building-beautiful-uis https://www.danvega.dev/blog/ui-dot-sh-agent-skills-for-building-beautiful-uis Tue, 07 Jul 2026 09:00:00 GMT Dan Vega AI Tailwind CSS Spring AI gives you two ways to call an LLM. Learn the difference between ChatClient and ChatModel, when to use each, and see both in action with code examples. https://www.danvega.dev/blog/chatclient-vs-chatmodel-spring-ai https://www.danvega.dev/blog/chatclient-vs-chatmodel-spring-ai Thu, 02 Jul 2026 09:00:00 GMT Dan Vega Spring AI Spring Boot X released MCP servers for its API and docs. Build a Spring Boot MCP client with Spring AI 2.0 to search X posts and query the X API docs programmatically. https://www.danvega.dev/blog/x-twitter-mcp-servers-spring-ai https://www.danvega.dev/blog/x-twitter-mcp-servers-spring-ai Wed, 01 Jul 2026 09:00:00 GMT Dan Vega Spring AI MCP Spring Boot Spring Boot 4.1 adds type-safe property paths to Spring Data, replacing stringly typed references in sorting, criteria queries, and composite paths. https://www.danvega.dev/blog/type-safe-property-paths-spring-boot-4-1 https://www.danvega.dev/blog/type-safe-property-paths-spring-boot-4-1 Tue, 30 Jun 2026 09:00:00 GMT Dan Vega Spring Boot Spring Data Spring Boot 4.1 adds @RedisListener, one annotation that brings Redis Pub/Sub in line with @KafkaListener and @RabbitListener. No container wiring needed. https://www.danvega.dev/blog/redis-listener-spring-boot-4-1 https://www.danvega.dev/blog/redis-listener-spring-boot-4-1 Mon, 29 Jun 2026 09:00:00 GMT Dan Vega Spring Boot Redis Learn how Spring Boot 4.1's new InetAddressFilter protects your applications against Server-Side Request Forgery (SSRF) attacks with a single bean definition. https://www.danvega.dev/blog/spring-boot-ssrf-protection-inet-address-filter https://www.danvega.dev/blog/spring-boot-ssrf-protection-inet-address-filter Fri, 26 Jun 2026 09:00:00 GMT Dan Vega Spring Boot Java Spring Boot 4.1 adds lazy JDBC connection fetching via spring.datasource.connection-fetch. See how it cuts connection hold time from 2 seconds to 15ms. https://www.danvega.dev/blog/lazy-jdbc-connections-spring-boot-4-1 https://www.danvega.dev/blog/lazy-jdbc-connections-spring-boot-4-1 Thu, 25 Jun 2026 09:00:00 GMT Dan Vega Spring Boot Spring Data Build a gRPC server and client in Spring Boot 4.1 with Spring gRPC — using @GrpcService, protobuf, and the new starters from start.spring.io. https://www.danvega.dev/blog/spring-grpc-spring-boot-4-1 https://www.danvega.dev/blog/spring-grpc-spring-boot-4-1 Wed, 24 Jun 2026 09:00:00 GMT Dan Vega Learn how to externalize Spring Modulith application events to Apache Kafka so other systems can react to changes happening inside your modular monolith. https://www.danvega.dev/blog/spring-modulith-externalized-events https://www.danvega.dev/blog/spring-modulith-externalized-events Wed, 20 May 2026 09:00:00 GMT Dan Vega Spring Modulith Produce and consume your first Apache Kafka message with Spring Boot. Covers Docker Compose, KafkaTemplate, @KafkaListener, and Embedded Kafka for tests. https://www.danvega.dev/blog/spring-boot-kafka-quick-start https://www.danvega.dev/blog/spring-boot-kafka-quick-start Mon, 18 May 2026 08:00:00 GMT Dan Vega Spring Boot Apache Kafka Spring for Apache Kafka Learn how Spring Modulith's event publication registry persists and replays failed events across restarts, giving you a transactional outbox with no message broker. https://www.danvega.dev/blog/spring-modulith-durable-events https://www.danvega.dev/blog/spring-modulith-durable-events Thu, 14 May 2026 09:00:00 GMT Dan Vega Spring Boot Spring Modulith Learn how Spring Modulith helps you build a modular monolith in Spring Boot with enforced module boundaries, application events, and verified architecture. https://www.danvega.dev/blog/introduction-to-spring-modulith https://www.danvega.dev/blog/introduction-to-spring-modulith Thu, 30 Apr 2026 09:00:00 GMT Dan Vega Spring Boot Spring Modulith Java Modular Monolith Add tools and MCP servers to your Embabel agents in Java. Build a blog writing agent that researches topics, calculates reading time, and generates front matter. https://www.danvega.dev/blog/embabel-mcp-servers-and-tools https://www.danvega.dev/blog/embabel-mcp-servers-and-tools Fri, 10 Apr 2026 08:00:00 GMT Dan Vega Spring AI Embabel Java A first look at Embabel, Rod Johnson's framework for building agentic AI flows on the JVM. Build a blog writing agent using goal-oriented action planning (GOAP). https://www.danvega.dev/blog/embabel-first-look https://www.danvega.dev/blog/embabel-first-look Thu, 02 Apr 2026 08:00:00 GMT Dan Vega Spring AI Java Build GraphQL APIs in Java with Spring Boot 4 and Spring for GraphQL. A free course covering schema-first design, batch loading, unions, and AOT repositories. https://www.danvega.dev/blog/getting-started-with-graphql-for-java-developers https://www.danvega.dev/blog/getting-started-with-graphql-for-java-developers Wed, 01 Apr 2026 08:00:00 GMT Dan Vega Spring Boot Java GraphQL Build an autonomous coding agent in Spring AI with the Spring AI Agent Utils library. This tutorial adds file system tools, shell commands, and agent skills. https://www.danvega.dev/blog/spring-building-me-a-coding-agent https://www.danvega.dev/blog/spring-building-me-a-coding-agent Tue, 31 Mar 2026 08:00:00 GMT Dan Vega Spring AI Spring Boot Java AI Agent Search https://www.danvega.dev/blog/spring-ai-deep-research-agent https://www.danvega.dev/blog/spring-ai-deep-research-agent Fri, 27 Mar 2026 09:00:00 GMT Dan Vega AI Learn best practices for error handling with Spring's RestClient, including global exception handlers, custom exceptions, Problem Detail responses, and built-in retry with resilience methods in Spring Framework 7. https://www.danvega.dev/blog/rest-client-error-handling https://www.danvega.dev/blog/rest-client-error-handling Thu, 26 Mar 2026 09:00:00 GMT Dan Vega Spring Boot Spring Framework REST Client Java Most AI agents can search the web. But what happens when they need to actually use it? I built a Spring Boot Starter for Browserbase that gives your agents a real, headless browser in three lines of configuration, plus a deep research agent to show it off. https://www.danvega.dev/blog/browserbase-spring-boot-starter https://www.danvega.dev/blog/browserbase-spring-boot-starter Wed, 25 Mar 2026 08:00:00 GMT Dan Vega Spring Boot Spring AI JDK 26 introduces JEP 500, which warns developers when final fields are mutated through reflection. Here's what this means for your Java code and how to prepare for the future. https://www.danvega.dev/blog/jdk-26-final-means-final https://www.danvega.dev/blog/jdk-26-final-means-final Fri, 20 Mar 2026 10:00:00 GMT Dan Vega Java How I built a terminal user interface for the Spring Initializr using Tambu UI, a new Java TUI framework, and GraalVM native images to streamline my development workflow. https://www.danvega.dev/blog/spring-initializr-tui https://www.danvega.dev/blog/spring-initializr-tui Sat, 14 Mar 2026 10:00:00 GMT Dan Vega Java Spring Boot Spring AI prompt caching cuts your Anthropic Claude API costs. Use AnthropicCacheStrategy to cache system prompts and tools that don't change between requests. https://www.danvega.dev/blog/spring-ai-prompt-caching https://www.danvega.dev/blog/spring-ai-prompt-caching Sun, 08 Feb 2026 09:00:00 GMT Dan Vega Spring AI OpenAI released Codex, a new GUI for their coding agent. I put it to the test by building a vending machine CLI application in Java 25 with Maven, JUnit 6, and JSpecify null safety annotations. https://www.danvega.dev/blog/openai-codex-first-look https://www.danvega.dev/blog/openai-codex-first-look Thu, 05 Feb 2026 09:00:00 GMT Dan Vega Java AI The Ralph Loop is a bash script that runs your AI coding agent with a fresh context every iteration. Here's how it works and how I used it to build a Java CLI. https://www.danvega.dev/blog/ralph-loop https://www.danvega.dev/blog/ralph-loop Thu, 05 Feb 2026 09:00:00 GMT Dan Vega AI Java Learn how to use the new spring-boot-starter-opentelemetry in Spring Boot 4 to add observability with traces, metrics, and logs—no Actuator required. https://www.danvega.dev/blog/opentelemetry-spring-boot https://www.danvega.dev/blog/opentelemetry-spring-boot Tue, 23 Dec 2025 09:00:00 GMT Dan Vega Spring Boot Observability Learn how to build a REST API with Spring Boot 4 in minutes. This tutorial shows you how to create CRUD endpoints using Java records and the @RestController annotation. https://www.danvega.dev/blog/spring-boot-4-rest-api https://www.danvega.dev/blog/spring-boot-4-rest-api Thu, 18 Dec 2025 09:00:00 GMT Dan Vega Spring Boot Java REST API Learn how to load resources in Spring Boot using the Resource interface. This tutorial covers three approaches for loading files from the classpath, filesystem, and URLs. https://www.danvega.dev/blog/loading-spring-resources https://www.danvega.dev/blog/loading-spring-resources Wed, 17 Dec 2025 09:00:00 GMT Dan Vega Spring Boot Spring Framework