My book: EffectOrientedProgramming.co… | My podcast: @HappyPathProg | @AWSCloud Agent Experience | @AgenticAIFdn TC | My opinions are mine

Joined February 2007
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The past 3 months have been the most intense and fruitful of my entire career. I've been cooking, coding, vibing, architecting, designing, imagining, and delivering production systems while teaching developers around the world how to build enterprise-grade AI systems. I'm on my way home from the amazing Spring I/O conference and reflecting on the seemingly insane number of things I've delivered / helped with over the past few months. Here are the most interesting: - SkillsJars: Agent Skills for the JVM ecosystem. Gaining rapid ecosystem adoption for enterprise needs. - javadocs.dev: Improvements for Java / Kotlin / Scala library Agent Experience (Valkey caching, more MCP tools, a new Scala ZIO HTTP MCP library to power it) - ai4jvm.com: A curated AI resource list for Java & Kotlin developers (along with a generalized approach to spec driven, AI assisted websites) - Spring AI AgentCore 1.0: The easy way to deliver enterprise-grade AI Agents & MCP servers on AWS - acp2web: Local code assistants available anywhere via ACP - MCP server for my Effect Oriented Programming book - MCP server for the Spring AI book that Josh Long are working on Along the way I presented and led hands-on Spring AI / Bedrock & MCP sessions at Jfokus, DevNexus, JavaOne, Voxxed Amsterdam, AI4J, Spring I/O, and GIDS in Bangalore next week. And I joined the Agentic AI Foundation Technical Committee, helping steer standards for the agentic world. It has been a wild ride and I'm loving how AI has empowered me to move at a pace that a year ago was inconceivable. There is much more to come and I’m grateful for the support and collaboration with so many amazing people!

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James Ward retweeted
🚀 Spring AI 2.0.0 GA is now available! 🏗️ Improved foundations: Spring Boot 4 baseline, null-safety, Jackson 3, re-designed options 🤖 Agentic improvements: unified tool calling, tool search, self-correcting output 🔌 MCP 2025-11-25 spec integration spring.io/blog/2026/06/12/sp…
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It is unbelievable how much better all software has become in the past 6 months! Like everything is working better! Fewer bugs. New features all the time! The apps I use every day have improved at least 10x from where they were just 6 months ago! Services I depend on never break. Oh wait. None of that happened. Almost everything is actually significantly worse. Not sure how to make sense of that given all the immense productivity gains. Actually I do. Regression to the mean has more gravity than ever. And that is not a good thing.
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Having my AI write some TypeScript and I now totally understand how some devs can use so many tokens.
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We are nearing a symbolic software/AI co-evolution!
Last week on Happy Path Programming, @JamesWard asked me whether AI helps with the proving side of Aver. I said no. In a meaning that AI writes Aver itself, but is not helping you to prove it later in any way. Today I think that answer was wrong - and weirdly, this is one of the most enjoyable times I’ve been wrong in a long time... In Aver, the same source file is both a program that runs and a set of laws exported to Lean 4 and Dafny/Z3. I’ve been growing the automatic prover by hand: adding strategies, improving induction cases, closing benchmark tasks one evening at a time. That works, but it scales with my evenings I'd rather spend with my kids on the playground. Meanwhile, LLM-driven proof search keeps improving. I was implicitly treating that as competition: better models generating more proofs, while I slowly grow a handwritten prover. Today, in a long session with Claude Fable 5, I finally saw the thing I had missed up to this point: Aver already has most of the shape of a trustworthy proof-candidate filter. A candidate law can go through cheap deterministic tests, hostile boundary inputs, Dafny/Z3, Lean, axiom counting, `sorry` checks, and fail-closed gates. The model’s confidence does not matter. The candidate either survives the pipeline or it does not. The only missing feature was almost hiding in plain sight... Aver’s `verify law` blocks are ALREADY A LEMMA LANGUAGE. But today the prover treats each law too much like a separate island. Proved laws should feed the lemma pool for later laws. The machinery is already close: last week I built lemma-pool plumbing for auto-discovered lemmas. The next step is to let already-proved user-written laws enter the same pool, with strict ordering and no cyclic dependency tricks, which opens a much more interesting loop. An LLM can try to decompose a hard theorem into small helper laws, directly in Aver, never touching generated Lean or Dafny. Bad candidates usually die in milliseconds on fast VM tests. Survivors go through the real, more expensive verifier chain. Only proved lemmas become available to the next proof attempt. So the fancy new Claude Fable 5 did not give me a magic proof, but it made me notice that the useful thing here is the pipeline around proof attempts: cheap generation, brutal filtering, and a final verdict that does not depend on trusting the generator. So I think my answer to James was wrong, but in a more interesting way than I expected: AI does not really help Aver’s proving side yet, but Aver may already have the right shape for making AI-written proof attempts useful without trusting them.
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All Aboard The Release Train -- Finally! x.com/i/broadcasts/1AGRnnpDy…

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All Aboard The Release Train -- Finally! x.com/i/broadcasts/1nxnRRzwg…

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James Ward retweeted
I hear more and more people worry that AI agents are getting closer to the level of human engineers. I’m more worried that more and more human engineers are getting closer to the level of AI agents.
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Lean proofs or it didn't happen!
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It is great to see Micronaut adding Scala support! Can anyone help Graeme review the compiler plugin code?
Dear @scala_lang community. This PR adds Scala support to @micronautfw github.com/micronaut-project… But here is the deal, AI was used in for this PR and I know nothing about Scala 3 compiler plugins nor does anyone else in the Micronaut team. Anybody wanna help? cc @JamesWard
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FDEs are a "round peg, square hole" approach. A better approach is Congruent AI tech. If the business system is already Java & Spring (which it likely is, if it is powering significant business value), then Spring AI is the solution, not FDEs.
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James Ward retweeted
Enjoying a great evening with splendid talks by @starbuxman, @JamesWard and @glyc1n, delicious food and amazing company. Thank you JetBrains for the giveaways. Big thanks to Keylane for hosting us. Till the next one! #utrecht #jug #java #community
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It was really fun talking to Szymon about AI-Native programming languages / Aver!
You know what's more surreal than building a language for AI to write and humans to read? Talking about it with @JamesWard and @BruceEckel in my second language, making hand gestures to explain language design choices. Thanks for having me on @HappyPathProg! youtu.be/D_mPxGtSzbQ
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It's been a bit but the Happy Path Programming podcast is back! @BruceEckel and I chat with @jasisz1 about Aver: The AI-native language where code explains itself.
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ya know what is more "agent friendly" than YAML? things with explicit schemas. bring back XML and XSD! :)
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James Ward retweeted
MCP is evolving for real-world agentic systems. @techgirl1908 (VP of Developer Experience, AAIF) breaks down the 2026-07-28 release candidate, where MCP shifts to a stateless protocol layer and makes state, capabilities, and extensions more explicit. The result is a tighter, more operationally sound foundation for scaling MCP deployments. Read more → bit.ly/4ec2Q0b
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Just a wild guess but I bet it was built in Python. Coincidence?
JUST IN: Starbucks retires AI inventory tool across North America after it reportedly miscounted & mislabeled store items.
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This is the most fun you can possibly have learning about building AI agents with Java and Amazon Bedrock! Guaranteed or your money back.
🍃 Bootiful Spring AI by @starbuxman / @JamesWard @ Spring I/O 2026 ▶️ Video: youtu.be/nHnKReitDXc #springio26
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Well I cooked up a @zioscala library for AI inference with Amazon Bedrock. Took quite a bit of churning to get to an API that I like. Check out the repo: github.com/jamesward/zio-bed… And the full sample: github.com/jamesward/hello-z…
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Effect Oriented Programming is crossing the chasm! But what even are Effects? Here is one way to look at it... I'm sure many developers are familiar with async functions where "function coloring" is a viral marker: everything that touches an async thing then becomes async itself. Here is the main idea of Effects: "async" is one color but there are others like errors, file IO, clock, random, etc. Anything that touches the world outside of its scope has a color. And everything that is a color can be combined into a rainbow. Rainbows are good because then your AI and your compiler know exactly what is needed and how it might fail. So if you have a 🟤 that touches a 🟩 then the composition is 🟤 🟩 which you want to know and keep track of. Effects are generalized function coloring, enabling reliable composition, fearless refactoring, explicit testability, and type system based understandability. 🌈 colored code is a superpower for you and your AI!
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