Short notes on Symfony, open source and agentic development. One observation at a time.https://johanneswachter.dev/enhttps://johanneswachter.dev/shorts/a-test-that-saves-object-numbers-tests-php/https://johanneswachter.dev/shorts/a-test-that-saves-object-numbers-tests-php/One added line in a Symfony AI pull request broke 25 tests without any assertion changing. The tests were checking something nobody meant to check.Sat, 10 Oct 2026 00:00:00 GMTphptestingsymfonyhttps://johanneswachter.dev/shorts/the-ai-feature-was-the-short-part/https://johanneswachter.dev/shorts/the-ai-feature-was-the-short-part/Live on Never Code Alone we set up Sulu AI Intelligent Search. The feature itself took a few commands. The rest was the project around it.Thu, 01 Oct 2026 00:00:00 GMTsuludeveloper-practicehttps://johanneswachter.dev/shorts/who-symfonys-new-bundles-are-actually-for/https://johanneswachter.dev/shorts/who-symfonys-new-bundles-are-actually-for/Symfony 8.2 is moving configuration out of FrameworkBundle and into 29 bundles shipped by the components that actually own it: Messenger, HttpClient, Cache, Scheduler, PropertyInfo and many others.Mon, 28 Sep 2026 00:00:00 GMTsymfonyphpagentic-aihttps://johanneswachter.dev/shorts/claude-code-now-falls-back-to-agents-md/https://johanneswachter.dev/shorts/claude-code-now-falls-back-to-agents-md/Claude Code 2.1.277 now checks for an AGENTS.md file whenever a folder has no CLAUDE.md (there's a toggle for it in /config).Wed, 23 Sep 2026 00:00:00 GMTaiagentic-aisymfonyhttps://johanneswachter.dev/shorts/somebody-still-has-to-read-it/https://johanneswachter.dev/shorts/somebody-still-has-to-read-it/A post proposing AI;DR hit #1 on Hacker News: if you didn't read and edit what the model produced, don't expect the author to read it either. Producing a wall of text became free.Sun, 20 Sep 2026 00:00:00 GMTaiwritingcode-reviewhttps://johanneswachter.dev/shorts/the-bug-agents-kept-finding-in-symfonys-makers/https://johanneswachter.dev/shorts/the-bug-agents-kept-finding-in-symfonys-makers/Twelve merged pull requests in one release, my first-ever contribution to Symfony's maker-bundle. All of them were about the same thing: agents kept running into make:* commands that only worked with a human answering prompts, and simply crashed otherwise.Sun, 13 Sep 2026 00:00:00 GMTsymfonyphpai-agentshttps://johanneswachter.dev/shorts/model-collapse-in-my-gradebook/https://johanneswachter.dev/shorts/model-collapse-in-my-gradebook/Coaching an innovation project this summer semester, one question had been sitting with me the whole time: whose idea was this, actually, and how much of it came from the model?Mon, 07 Sep 2026 00:00:00 GMTaiteachinghttps://johanneswachter.dev/shorts/symfony-language-tools-stopped-taking-patches/https://johanneswachter.dev/shorts/symfony-language-tools-stopped-taking-patches/Symfony's new Language Tools repository closed its pull request tab. Contributors now start with an issue instead. Maintainers turn selected issues into code, usually with a coding agent doing much of the implementation work. Fabien's reasoning is what stuck with me.Fri, 04 Sep 2026 00:00:00 GMTsymfonyopen-sourceaihttps://johanneswachter.dev/shorts/roots-shipped-inside-its-own-deprecation-window/https://johanneswachter.dev/shorts/roots-shipped-inside-its-own-deprecation-window/MCP's 2026-07-28 specification deprecated Roots, Sampling and Logging, with at least twelve months before they become eligible for removal. On August 14th, my Roots support PR merged into the official PHP SDK. None of this was hidden.Sun, 30 Aug 2026 00:00:00 GMTmcpphpopen-sourcehttps://johanneswachter.dev/shorts/mates-mcp-server-is-gone/https://johanneswachter.dev/shorts/mates-mcp-server-is-gone/symfony/ai 0.13 shipped today, my first release as a core team member. The headline change for Mate is PR #2380: Mate drops its MCP server entirely and becomes a plain CLI with a discovery layer on top.Sat, 29 Aug 2026 00:00:00 GMTsymfonyaimatehttps://johanneswachter.dev/shorts/being-neutral-is-easier-without-a-price-tag/https://johanneswachter.dev/shorts/being-neutral-is-easier-without-a-price-tag/Nvidia has reportedly agreed to buy Hugging Face for 12.9 billion dollars, according to The Information. Other reports put the talks above 13 billion, with no deal signed yet. Neither company has confirmed it. What catches me isn't the price, it's the buyer.Fri, 28 Aug 2026 00:00:00 GMTaiopen-sourcehttps://johanneswachter.dev/shorts/the-passport-isnt-the-point/https://johanneswachter.dev/shorts/the-passport-isnt-the-point/A growing argument on my feed: switch to Chinese AI models, because they ship open weights and open beats closed. Open weights are a real property. You can download the file, inspect it, run it yourself. What they don't guarantee is what's actually baked into the answers.Thu, 27 Aug 2026 00:00:00 GMTaiopen-sourcehttps://johanneswachter.dev/shorts/context-engineering-for-claude-5/https://johanneswachter.dev/shorts/context-engineering-for-claude-5/Anthropic cut more than 80% of Claude Code's system prompt for the Claude 5 generation models, with no drop in coding evals. What interests me isn't the number.Tue, 25 Aug 2026 00:00:00 GMTaiagentic-aicontext-engineeringhttps://johanneswachter.dev/shorts/nobody-has-the-answers-yet/https://johanneswachter.dev/shorts/nobody-has-the-answers-yet/A post going around traces this back to something Kent Beck keeps repeating on his podcast "Still Burning": nobody has the answers.Tue, 25 Aug 2026 00:00:00 GMTaiagentic-aihttps://johanneswachter.dev/shorts/no-single-message-says-the-dangerous-part/https://johanneswachter.dev/shorts/no-single-message-says-the-dangerous-part/A disclosed technique called GhostSplice shows that an MCP server does not need to put anything obviously dangerous in a single message.Sun, 23 Aug 2026 00:00:00 GMTaimcpsecurityhttps://johanneswachter.dev/shorts/the-repository-was-the-easy-part/https://johanneswachter.dev/shorts/the-repository-was-the-easy-part/GitHub spent almost eight hours on Monday returning errors across git operations, pull requests, Actions, Pages and Copilot. By the afternoon an Ask HN thread about alternatives to GitHub was on the front page with a few hundred comments.Thu, 20 Aug 2026 00:00:00 GMTopen-sourcedeveloper-toolingaihttps://johanneswachter.dev/shorts/manufacture-everything-except-ownership/https://johanneswachter.dev/shorts/manufacture-everything-except-ownership/Helge Sverre had Claude and Suno write a song about a coding agent slowly taking over a team's daily standup. One line in the second verse says more than most articles on the subject.Tue, 18 Aug 2026 00:00:00 GMTaiagentic-aiculturehttps://johanneswachter.dev/shorts/rector-extension-for-symfony-mate/https://johanneswachter.dev/shorts/rector-extension-for-symfony-mate/The new Rector extension for Symfony Mate splits one tool into two: rector-preview runs dry-run enforced and cannot write, rector-apply is a separate tool that announces itself as a write operation. Inspecting code is never the thing that changes it. Contributed by mdjdev, not by me.Tue, 18 Aug 2026 00:00:00 GMTmatephpaihttps://johanneswachter.dev/shorts/first-merge-in-symfony-ai/https://johanneswachter.dev/shorts/first-merge-in-symfony-ai/For the first time, I merged a pull request in symfony/ai myself. It was a small fix and not mine, PR #2404, the kind of change that takes a minute to read and no time at all to agree with.Mon, 17 Aug 2026 00:00:00 GMTsymfonyaicareerhttps://johanneswachter.dev/shorts/the-symfony-lsp-and-who-wrote-it/https://johanneswachter.dev/shorts/the-symfony-lsp-and-who-wrote-it/Symfony's new official LSP server ships with a disclosure most projects still keep private: most of the code was written and reviewed by AI models.Mon, 17 Aug 2026 00:00:00 GMTsymfonyaiopen-source