[{"data":1,"prerenderedAt":804},["ShallowReactive",2],{"blog-post-/blogs/proving-where-data-stops-integration-debugging":3,"blog-list":509},{"id":4,"title":5,"body":6,"description":490,"extension":491,"meta":492,"navigation":152,"ogImage":504,"path":505,"seo":506,"stem":507,"__hash__":508},"content/blogs/27. proving-where-data-stops-integration-debugging.md","Proving Where Data Stops — How I Debug Multi-System Integrations",{"type":7,"value":8,"toc":480},"minimark",[9,13,21,26,69,73,80,95,98,208,219,222,225,229,232,239,311,327,334,338,352,355,358,362,369,388,391,395,398,405,408,411,415,449,458,462,476],[10,11,12],"p",{},"Most \"the shop is broken\" tickets aren't about the shop. A value comes from a PIM, passes through an export job, an upload, a connector, a database, a cache and a CDN, and shows up wrong on a product page. Every team in that chain has a reasonable theory that the problem is somewhere else. The ticket then ping-pongs for days, because everyone argues from opinion.",[10,14,15,16,20],{},"I stopped arguing a while ago. The job is to ",[17,18,19],"strong",{},"prove where the data stops"," — find the last hop where it was still correct and the first hop where it isn't — and hand that over as something reproducible. Five cases from the past few weeks, anonymized, show what that looks like.",[22,23,25],"h2",{"id":24},"the-method","The Method",[27,28,29,36,42,48,63],"ol",{},[30,31,32,35],"li",{},[17,33,34],{},"Write down the hops."," Source system, export, transport, import, storage, delivery. If you can't list them, you can't bisect them.",[30,37,38,41],{},[17,39,40],{},"Look at the boundary, not the middle."," At each handoff, check what actually crossed: the raw file, the HTTP response, the row. Not the log line that says \"success\".",[30,43,44,47],{},[17,45,46],{},"Bisect."," Pick the hop in the middle, check, discard half the chain. Repeat.",[30,49,50,53,54,58,59,62],{},[17,51,52],{},"Make the break reproducible."," One ",[55,56,57],"code",{},"curl",", one SQL query, one ",[55,60,61],{},"grep",". Something the other team can run themselves.",[30,64,65,68],{},[17,66,67],{},"Say what you did not verify."," An assumption labeled as an assumption is useful. An assumption presented as a finding costs you credibility.",[22,70,72],{"id":71},"case-1-the-field-that-was-never-sent","Case 1: The Field That Was Never Sent",[10,74,75,76,79],{},"A Shopware 5 B2B shop imports articles from a PIM through a connector. The PIM export has a ",[55,77,78],{},"new_date"," column; the connector maps it to the article's listing date and each variant's release date. The client's PIM team changed an article to test the field and saw nothing change in the backend. Their suspicion: the import drops the value.",[10,81,82,83,86,87,90,91,94],{},"I read the deployed connector first (not the branch I had been experimenting on — I verified the working tree was clean and matched what runs on production). The mapping is straightforward: empty or ",[55,84,85],{},"NOS"," falls back to ",[55,88,89],{},"2000-01-01",", and the screenshot showed exactly ",[55,92,93],{},"01.01.2000",". That fit two stories: the value arrives empty, or the import loses it. The code can't tell you which. The server can.",[10,96,97],{},"On production, read-only:",[99,100,105],"pre",{"className":101,"code":102,"language":103,"meta":104,"style":104},"language-bash shiki shiki-themes github-dark","# newest uploaded delivery\nls -t uploads/data_*.xml | head -1\n\n# what did the field look like for the test article, and for the whole file?\ngrep -c '\u003Cnew_date/>' uploads/data_*.xml\ngrep -o '\u003Cnew_date>[^\u003C]*\u003C/new_date>' uploads/data_*.xml | sort | uniq -c\n","bash","",[55,106,107,116,147,154,160,178],{"__ignoreMap":104},[108,109,112],"span",{"class":110,"line":111},"line",1,[108,113,115],{"class":114},"sAwPA","# newest uploaded delivery\n",[108,117,119,123,127,131,134,137,141,144],{"class":110,"line":118},2,[108,120,122],{"class":121},"svObZ","ls",[108,124,126],{"class":125},"sDLfK"," -t",[108,128,130],{"class":129},"sU2Wk"," uploads/data_",[108,132,133],{"class":125},"*",[108,135,136],{"class":129},".xml",[108,138,140],{"class":139},"snl16"," |",[108,142,143],{"class":121}," head",[108,145,146],{"class":125}," -1\n",[108,148,150],{"class":110,"line":149},3,[108,151,153],{"emptyLinePlaceholder":152},true,"\n",[108,155,157],{"class":110,"line":156},4,[108,158,159],{"class":114},"# what did the field look like for the test article, and for the whole file?\n",[108,161,163,165,168,171,173,175],{"class":110,"line":162},5,[108,164,61],{"class":121},[108,166,167],{"class":125}," -c",[108,169,170],{"class":129}," '\u003Cnew_date/>'",[108,172,130],{"class":129},[108,174,133],{"class":125},[108,176,177],{"class":129},".xml\n",[108,179,181,183,186,189,191,193,195,197,200,202,205],{"class":110,"line":180},6,[108,182,61],{"class":121},[108,184,185],{"class":125}," -o",[108,187,188],{"class":129}," '\u003Cnew_date>[^\u003C]*\u003C/new_date>'",[108,190,130],{"class":129},[108,192,133],{"class":125},[108,194,136],{"class":129},[108,196,140],{"class":139},[108,198,199],{"class":121}," sort",[108,201,140],{"class":139},[108,203,204],{"class":121}," uniq",[108,206,207],{"class":125}," -c\n",[10,209,210,211,214,215,218],{},"The newest delivery contained the test article with an ",[17,212,213],{},"empty"," ",[55,216,217],{},"\u003Cnew_date/>"," element, and so did every other entry in the file. The import hadn't lost anything; the field was empty before it reached us. The PIM team later confirmed it: the value had been exported up to some point in the past and had been \"forgotten\" since.",[10,220,221],{},"The second finding came from asking \"is that really the last import?\" — the client had asked, and I rechecked rather than repeating myself. The newest upload file, the newest import log, the connector's own log, and the access log for the upload-finished webhook all pointed to the same single run days earlier, with nothing after it. Four independent sources agreeing is evidence. One log file is a guess.",[10,223,224],{},"The answer to the client was a table of what I checked and what each check showed, not an explanation of how the import \"should\" behave.",[22,226,228],{"id":227},"case-2-images-that-live-on-the-wrong-side-of-a-bucket","Case 2: Images That Live on the Wrong Side of a Bucket",[10,230,231],{},"A price-monitoring tool shows dealer logos on product pages. The logos were served through the shop's image CDN, and they didn't load. They seemed to live in an old object-storage bucket; I had been about to build a fallback for the old path.",[10,233,234,235,238],{},"A fallback is a code change based on a theory. A ",[55,236,237],{},"HEAD"," request is a fact:",[99,240,242],{"className":101,"code":241,"language":103,"meta":104,"style":104},"curl -sI https://\u003Cold-bucket>.s3.amazonaws.com/media/DATA/Dealers/\u003Cname>.png\n# HTTP 200, content-type image/png, ~31 kB, last-modified: months ago\n\ncurl -sI https://cdn.example.com/media/300x300/DATA/Dealers/\u003Cname>.png\n",[55,243,244,283,288,292],{"__ignoreMap":104},[108,245,246,248,251,254,257,260,264,267,270,272,275,278,280],{"class":110,"line":111},[108,247,57],{"class":121},[108,249,250],{"class":125}," -sI",[108,252,253],{"class":129}," https://",[108,255,256],{"class":139},"\u003C",[108,258,259],{"class":129},"old-bucke",[108,261,263],{"class":262},"s95oV","t",[108,265,266],{"class":139},">",[108,268,269],{"class":129},".s3.amazonaws.com/media/DATA/Dealers/",[108,271,256],{"class":139},[108,273,274],{"class":129},"nam",[108,276,277],{"class":262},"e",[108,279,266],{"class":139},[108,281,282],{"class":129},".png\n",[108,284,285],{"class":110,"line":118},[108,286,287],{"class":114},"# HTTP 200, content-type image/png, ~31 kB, last-modified: months ago\n",[108,289,290],{"class":110,"line":149},[108,291,153],{"emptyLinePlaceholder":152},[108,293,294,296,298,301,303,305,307,309],{"class":110,"line":156},[108,295,57],{"class":121},[108,297,250],{"class":125},[108,299,300],{"class":129}," https://cdn.example.com/media/300x300/DATA/Dealers/",[108,302,256],{"class":139},[108,304,274],{"class":129},[108,306,277],{"class":262},[108,308,266],{"class":139},[108,310,282],{"class":129},[10,312,313,314,317,318,322,323,326],{},"The logos existed under the key prefix ",[55,315,316],{},"media/DATA/Dealers/",". The CDN resolves a request to the same key in the ",[319,320,321],"em",{},"new"," bucket; ",[55,324,325],{},"300x300"," is only an image-proxy resize segment and not part of the key. So the question to the infrastructure owner wasn't \"can you fix the CDN?\" but \"move this exact prefix with identical keys, then neither fallback nor code change is needed.\" The infra side had already found the fallback wouldn't work anyway, because the paths inside the two buckets weren't the same. The proof turned a speculative code change into one concrete migration.",[10,328,329,330,333],{},"A side finding I flagged instead of burying: the CDN URL returned 200 with and without the size segment, but no ",[55,331,332],{},"content-type"," header, so \"it returns 200\" did not prove \"it returns an image\". I only read headers, and I said so.",[22,335,337],{"id":336},"case-3-wrong-image-in-the-listing-is-a-fallback-question","Case 3: \"Wrong Image in the Listing\" Is a Fallback Question",[10,339,340,341,344,345,348,349,351],{},"A Shopware 6 shop had questions about which product image shows up where, and whether the import picks the ",[55,342,343],{},"_01"," view as cover. Before touching data, I read how the images get there. In this project the import sets the cover only from the PIM's dedicated cover field; the gallery comes from the ",[55,346,347],{},"images"," and action-image fields. The file name never matters — a ",[55,350,343],{}," suffix is irrelevant. If a product has no cover from the PIM, it has none, and an existing cover isn't replaced by a later import.",[10,353,354],{},"Then the storefront: some components fall back to the first media entry, some only read the cover, and one component I was asked to fix turned out to be unused entirely — a search for it by name, in kebab-case and in the template tag, found no usage. Earlier in the session I had claimed that the search flyout showed no image. That was wrong: the real flyout goes through the product card, which has the fallback. I corrected it in the next message instead of defending it.",[10,356,357],{},"The lesson is that image bugs in listings are rarely a rendering bug. They're a data contract: which field is authoritative, who writes it, and what each consumer does when it's empty. Once that table exists, the reproduction is straightforward: remove the cover on one product on a test system and watch which components degrade.",[22,359,361],{"id":360},"case-4-a-new-endpoint-and-the-review-comment-that-was-right","Case 4: A New Endpoint, and the Review Comment That Was Right",[10,363,364,365,368],{},"A new API endpoint was needed that lists all active product numbers in one sales channel. My first version followed the ticket: respect inheritance, so a variant with ",[55,366,367],{},"active = NULL"," takes the parent's value and a variant without visibility rows takes the parent's. It matched the reference query from the ticket, with the same count locally.",[10,370,371,372,375,376,379,380,383,384,387],{},"The reviewer pointed out that this shop doesn't use Shopware variants at all — every \"variant\" is a standalone product with its own ",[55,373,374],{},"active"," flag and its own visibility. The parent join, the ",[55,377,378],{},"COALESCE"," and the ",[55,381,382],{},"EXISTS"," were solving a problem the data model doesn't have. Matching the reference query only proved I'd implemented the ticket as written; it didn't prove the ticket matched the data. I reduced the query to ",[55,385,386],{},"p.active = 1"," plus the product's own visibility for the channel.",[10,389,390],{},"I also noted the limit of the test: it mocks the DB connection, so it checks the SQL condition, not the data. Say that out loud when you write the PR description.",[22,392,394],{"id":393},"case-5-api-limit-or-webserver-bug","Case 5: \"API Limit or Webserver Bug?\"",[10,396,397],{},"A web service syncs shop admin credentials into a password manager, and entries were randomly missing. The hypothesis everyone had: rate limit. I measured it instead — a full sync of a single user created 36 items in roughly 30 seconds with no 429 and no error. Not a limit.",[10,399,400,401,404],{},"What the data did show: the join table that the sync requires had rows missing for many user/shop pairs, and without a row the sync silently returns ",[55,402,403],{},"false"," and creates nothing. On production, one user was missing 8 of 44 rows. The cause was an admin hook that, when editing one category, rewrote assignments using only that category's users and deleted the rows of everyone else. A second bug created extra shop URLs as custom fields rather than real website URLs, which is why the password manager's domain matching favored the wrong entries — though I labeled the exact suggestion ordering as an assumption because I hadn't tested the extension's logic.",[10,406,407],{},"There was an infrastructure finding too: a cron cleared the log file every 15 minutes, so the errors were gone before anyone could read them, and there was no failure transport, so failed messages vanished after their retries. Part of \"proving where data stops\" is making sure the next investigation has evidence to read.",[10,409,410],{},"The fix and unit tests (one of which fails without the fix) went on a separate branch for a pull request, because the main branch was protected. What I couldn't test was the admin UI and the browser behavior, and the report said so.",[22,412,414],{"id":413},"what-the-cases-share","What the Cases Share",[416,417,418,424,437,443],"ul",{},[30,419,420,423],{},[17,421,422],{},"The break was always at a boundary",": an export, a bucket, a data model, a join table. Never \"in the middle\".",[30,425,426,429,430,432,433,436],{},[17,427,428],{},"The evidence was cheap",": ",[55,431,61],{},", ",[55,434,435],{},"curl -I",", one SQL count, a file timestamp.",[30,438,439,442],{},[17,440,441],{},"Every report listed what I had not checked."," It makes the checked part believable.",[30,444,445,448],{},[17,446,447],{},"I got things wrong along the way"," (the search flyout claim, the variant inheritance). Writing the reproduction made the error visible quickly.",[10,450,451,452,457],{},"If you're running an integration landscape that fails in ways nobody can explain, ",[453,454,456],"a",{"href":455},"/contact","get in touch",".",[22,459,461],{"id":460},"related-posts","Related Posts",[416,463,464,470],{},[30,465,466],{},[453,467,469],{"href":468},"/blogs/claude-code-freelance-workflows","Claude Code in Real Client Work — Workflows, MCP, and Where It Breaks",[30,471,472],{},[453,473,475],{"href":474},"/blogs/1password-claude-agentic-security","1Password for Claude — Agents That Log In Without Seeing Your Password",[477,478,479],"style",{},"html pre.shiki code .sAwPA, html code.shiki .sAwPA{--shiki-default:#8B949E}html pre.shiki code .svObZ, html code.shiki .svObZ{--shiki-default:#B392F0}html pre.shiki code .sDLfK, html code.shiki .sDLfK{--shiki-default:#79B8FF}html pre.shiki code .sU2Wk, html code.shiki .sU2Wk{--shiki-default:#9ECBFF}html pre.shiki code .snl16, html code.shiki .snl16{--shiki-default:#F97583}html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html pre.shiki code .s95oV, html code.shiki .s95oV{--shiki-default:#E1E4E8}",{"title":104,"searchDepth":118,"depth":118,"links":481},[482,483,484,485,486,487,488,489],{"id":24,"depth":118,"text":25},{"id":71,"depth":118,"text":72},{"id":227,"depth":118,"text":228},{"id":336,"depth":118,"text":337},{"id":360,"depth":118,"text":361},{"id":393,"depth":118,"text":394},{"id":413,"depth":118,"text":414},{"id":460,"depth":118,"text":461},"A shop field that never updates, a CDN that can't find its images, a sync that \"randomly\" skips entries. A method for multi-system integrations — instrument every hop, read the boundary evidence, hand over proof instead of opinions — with five real cases from the last weeks.","md",{"seoTitle":493,"date":494,"image":495,"imageWidth":496,"imageHeight":497,"alt":498,"tags":499,"author":502,"published":152,"featured":503},"Integration Debugging - Prove Where Data Stops","05.10.2026","/blogs-img/integration-debugging.webp",1536,1024,"Data pipeline across four connected systems with a check at every hop and one orange marker where the data flow breaks",[500,501],"best-practices","devops","Marco Faul",false,"/blogs-img/integration-debugging.png","/blogs/proving-where-data-stops-integration-debugging",{"title":5,"description":490},"blogs/27. proving-where-data-stops-integration-debugging","Nt4kCgakTzvSWn88Z5DbxI5drOBfCKBPmyuJiJYogZw",[510,521,532,542,552,563,574,583,592,602,612,621,630,639,648,655,664,674,684,694,697,706,717,726,736,747,756,765,774,784,794],{"path":511,"title":512,"description":513,"meta":514},"/blogs/shopware-6-performance-guide","Shopware 6 Developer Performance Guide - Essential Improvements and Fixes","Performance optimization is crucial for any e-commerce platform. 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Learn the Vue Starter Template, Nuxt layers, composables, and the Store API architecture.",{"seoTitle":526,"date":527,"image":528,"imageWidth":496,"imageHeight":497,"alt":529,"tags":530,"author":502,"published":152,"featured":503},"Shopware Frontends - Composable Storefronts","06.06.2026","/blogs-img/shopware-frontends.webp","Shopware Frontends composable storefront with Vue and Nuxt",[519,531],"frontend",{"path":533,"title":534,"description":535,"meta":536},"/blogs/headless-shopware-cost","What Does a Headless Shopware Store Really Cost? A Realistic 2026 Breakdown","Thinking about going headless with Shopware? 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As a developer who relies on AI agents daily, the harness deserves far more scrutiny than we give it.",{"seoTitle":568,"date":569,"image":570,"imageWidth":496,"imageHeight":497,"alt":571,"tags":572,"author":502,"published":152,"featured":152},"AI Coding - The Harness Beats the Model","12.06.2026","/blogs-img/harness-vs-model.webp","AI model connected to a codebase through a harness bridge",[573,501],"ai",{"path":575,"title":576,"description":577,"meta":578},"/blogs/oh-my-pi","Oh My Pi — The Open-Source Coding Agent I Actually Use Every Day","Oh My Pi is a fork of Mario Zechner's Pi coding agent with ~1,300 commits of incremental improvements. Here's what makes it different, why harness quality shapes agent reliability more than model choice, and why I run it instead of Claude Code.",{"seoTitle":579,"date":569,"image":580,"imageWidth":496,"imageHeight":497,"alt":581,"tags":582,"author":502,"published":152,"featured":503},"Oh My Pi - My Daily Open-Source Coding Agent","/blogs-img/oh-my-pi.webp","Oh My Pi open-source coding agent harness with flowing code streams",[573,501],{"path":474,"title":584,"description":585,"meta":586},"1Password for Claude - AI Agents That Log In Without Ever Seeing Your Password","1Password and Anthropic shipped a zero-exposure integration that lets Claude log into websites and finish real tasks without the model ever touching a credential. 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Here's what actually matters, what to test before upgrading, and why the Nuxt 3 clock is about to run out.",{"seoTitle":597,"date":598,"image":599,"imageWidth":496,"imageHeight":497,"alt":600,"tags":601,"author":502,"published":152,"featured":503},"Nuxt 4.5 - Vite 8 and the Road to Nuxt 5","18.07.2026","/blogs-img/nuxt-4-5.webp","Nuxt 4.5 release - Vite 8, Rspack 2, SSR streaming and the road to Nuxt 5",[531,501],{"path":603,"title":604,"description":605,"meta":606},"/blogs/netlify-cloudflare-cache-purge","Purging Cloudflare's Cache Automatically on Every Netlify Deploy","This site sits on Netlify behind Cloudflare, and after every deploy Cloudflare kept serving stale HTML. Here's why the Netlify-CDN-Cache-Control header was a dead end for static files, and the 26-line build plugin that purges Cloudflare's edge cache the moment a deploy goes live — including the CJS/ESM gotcha that broke the first build.",{"seoTitle":607,"date":608,"image":609,"imageWidth":496,"imageHeight":497,"alt":610,"tags":611,"author":502,"published":152,"featured":503},"Auto-Purge Cloudflare Cache on Netlify Deploys","22.07.2026","/blogs-img/netlify-cloudflare-purge.webp","Netlify deploy triggering an automatic Cloudflare edge cache purge",[520,501],{"path":613,"title":614,"description":615,"meta":616},"/blogs/lcp-debugging-case-study","Debugging LCP on a Real Site - A Case Study on marcofaul.de","A first-person walkthrough of fixing LCP on this very site - a JS reveal animation gating first paint, a font preload that held rendering hostage, a 5.8s image CDN cold start, and the measurement noise that almost sent me chasing ghosts.",{"seoTitle":617,"date":608,"image":618,"imageWidth":496,"imageHeight":497,"alt":619,"tags":620,"author":502,"published":152,"featured":503},"Debugging LCP - A Real-World Case Study","/blogs-img/lcp-debugging.webp","Debugging Largest Contentful Paint - a real-world case study on marcofaul.de",[520,531],{"path":622,"title":623,"description":624,"meta":625},"/blogs/clean-code-summary-robert-martin","Summary of Clean Code by Robert C. Martin - Essential Guidelines for Better Software","Code is clean if it can be understood easily by everyone on the team. A comprehensive summary of Robert C. Martin's Clean Code principles and best practices.",{"seoTitle":626,"date":627,"image":628,"imageWidth":496,"imageHeight":497,"alt":623,"tags":629,"published":152,"featured":503},"Clean Code by Robert C. Martin - Summary","25.10.2025","/blogs-img/clean-code.webp",[500],{"path":631,"title":632,"description":633,"meta":634},"/blogs/pg-boss-10-to-12-upgrade","Upgrading pg-boss 10 → 12 When There Is No Migration Path","pg-boss 12 cannot migrate a v10 schema - v11 moved job storage to partitioned tables and the migration chain starts after that cliff. Here's how I upgraded a production job queue anyway - drop the schema, rebuild queue state from my own tables, and the job-ownership guard the rollout taught me to add.",{"seoTitle":635,"date":608,"image":636,"imageWidth":496,"imageHeight":497,"alt":637,"tags":638,"author":502,"published":152,"featured":503},"pg-boss 10 to 12 Upgrade Without a Migration Path","/blogs-img/pg-boss-upgrade.webp","Postgres-backed job queue being rebuilt during a pg-boss major version upgrade",[500,501],{"path":640,"title":641,"description":642,"meta":643},"/blogs/building-an-seo-crawler","I Built My Own SEO Crawler - Architecture Notes from seo-pulse","Instead of paying for Screaming Frog or Ahrefs, I built my own SEO audit tool - a Bun monorepo with a Nuxt 4 UI, a pg-boss worker that crawls and scores sites, and an MCP server so AI agents can trigger crawls and read findings. Here's the real architecture, and the parts that hurt - deploys killing workers mid-crawl, queue schema upgrades, and Docker builds dying without an error.",{"seoTitle":644,"date":608,"image":645,"imageWidth":496,"imageHeight":497,"alt":646,"tags":647,"author":502,"published":152,"featured":503},"Building an SEO Crawler - Architecture Notes","/blogs-img/seo-pulse-crawler.webp","Architecture diagram of a self-hosted SEO crawler with web app, Postgres queue, and worker",[573,501],{"path":468,"title":469,"description":649,"meta":650},"A year of running Claude Code on actual freelance and agency projects — the workflows that hold up, why MCP is the real game changer for client work, the failure modes nobody puts in demos, and what I promise clients about AI-assisted development.",{"seoTitle":651,"date":608,"image":652,"imageWidth":496,"imageHeight":497,"alt":653,"tags":654,"author":502,"published":152,"featured":503},"Claude Code in Freelance Work - Workflows & Limits","/blogs-img/claude-code-workflows.webp","AI coding agent connected to real project tooling in a client development workflow",[573,501],{"path":656,"title":657,"description":658,"meta":659},"/blogs/shopware-mcp-ai-agents","Shopware 6 Meets AI Agents - What an MCP Server for Your Shop Could Do","MCP gives AI agents a standard way to talk to real systems. Here's what an MCP server over Shopware's Admin API could look like - the tool surface, the architecture, and the honest risks of letting an agent near a live shop.",{"seoTitle":660,"date":608,"image":661,"imageWidth":496,"imageHeight":497,"alt":662,"tags":663,"author":502,"published":152,"featured":152},"Shopware 6 + AI Agents - An MCP Server for Your Shop","/blogs-img/shopware-mcp.webp","AI agent connected to a Shopware 6 shop through an MCP server",[519,573],{"path":665,"title":666,"description":667,"meta":668},"/blogs/jtl-to-shopify-migration","Migrating a JTL-Shop to Shopify: What to Import and What to Skip","There is no one-click connector from JTL-Shop to Shopify. Here is how I planned a real migration - what I imported, what I deliberately did not, how scripts verify the result, how to stop notification mails during an order import, and the launch checklist.",{"seoTitle":669,"date":670,"image":671,"imageWidth":496,"imageHeight":497,"alt":672,"tags":673,"author":502,"published":152,"featured":503},"JTL-Shop to Shopify Migration: Plan and Verify","06.10.2026","/blogs-img/jtl-shopify-migration.webp","Legacy shop with an encrypted database feeding a verified import pipeline into a Shopify storefront",[573,501],{"path":675,"title":676,"description":677,"meta":678},"/blogs/shopware-configurator-share-links","Shareable Product Configurator in Shopware 6 — State in the URL","How I built a product configurator for a Shopware 6 storefront where the whole state lives in a ?cfg= URL parameter — what to serialize, how the PDF export works, what breaks, and the trade-offs of letting users edit a shared configuration.",{"seoTitle":679,"date":680,"image":681,"imageWidth":496,"imageHeight":497,"alt":682,"tags":683,"author":502,"published":152,"featured":503},"Shopware 6 Configurator: Share Links & PDF Export","02.10.2026","/blogs-img/shopware-configurator.webp","Product configurator card whose state is encoded into a share link that fans out to a phone, a PDF and an email, with an orange loop marking the edit-a-shared-state problem",[519,531],{"path":685,"title":686,"description":687,"meta":688},"/blogs/shopify-personalized-products-and-packaging-fees","Personalized Products and Packaging Fees in Shopify","How I modeled printed cups with tiered prices and a logo upload in Shopify, and the options I weighed for passing a per-item packaging licence fee through to customers — with the pitfalls I hit.",{"seoTitle":689,"date":690,"image":691,"imageWidth":496,"imageHeight":497,"alt":692,"tags":693,"author":502,"published":152,"featured":503},"Shopify Personalized Products & Packaging Fees","04.10.2026","/blogs-img/shopify-personalization.webp","Product configurator with size and quantity tiles and a logo upload, next to a cart that separates a regulatory packaging fee line",[500,501],{"path":505,"title":5,"description":490,"meta":695},{"seoTitle":493,"date":494,"image":495,"imageWidth":496,"imageHeight":497,"alt":498,"tags":696,"author":502,"published":152,"featured":503},[500,501],{"path":698,"title":699,"description":700,"meta":701},"/blogs/scheduled-ai-agents-lessons","Scheduled AI Agents — What Weeks of Unattended Runs Teach You","Notes from running scheduled, unattended AI agents for a few weeks — a daily upstream-sync job, a research agent that publishes a page, and review-bot tuning. Guards, state files, failing publish steps, and where it breaks.",{"seoTitle":702,"date":670,"image":703,"imageWidth":496,"imageHeight":497,"alt":704,"tags":705,"author":502,"published":152,"featured":503},"Scheduled AI Agents: Lessons From Unattended Runs","/blogs-img/scheduled-agents.webp","Scheduled agent runs flowing through a guard into a published page, with one failing publish step highlighted",[573,501],{"path":707,"title":708,"description":709,"meta":710},"/blogs/bfsg-accessibility-online-shops","BFSG for Online Shops — What an Accessibility Audit Actually Finds","The BFSG has applied to B2C online shops since 28 June 2025. What an accessibility audit on a real headless Shopware storefront turned up, which fixes a developer can ship right away, which ones need design sign-off, and a checklist for your own shop.",{"seoTitle":711,"date":712,"image":713,"imageWidth":496,"imageHeight":497,"alt":714,"tags":715,"author":502,"published":152,"featured":503},"BFSG for Online Shops: Real Audit Findings","14.10.2026","/blogs-img/bfsg-accessibility.webp","Online shop wireframe with keyboard focus moving through header buttons, navigation and a product card, each checked against an accessibility list",[716,531],"accessibility",{"path":718,"title":719,"description":720,"meta":721},"/blogs/shopware-decoration-best-practices","Shopware Decoration Best Practices: Override One Method, Keep Others Untouched","Learn the golden rule of Shopware decorations - how to efficiently override only what you need while letting PHP inheritance handle the rest automatically.",{"seoTitle":722,"date":723,"image":724,"imageWidth":496,"imageHeight":497,"alt":719,"tags":725,"author":502,"published":152,"featured":152},"Shopware 6 Decoration Best Practices","26.10.2025","/blogs-img/shopware-decoration.webp",[519,500],{"path":727,"title":728,"description":729,"meta":730},"/blogs/storefront-requests-531-to-101","531 Requests on a Homepage — Cutting a Headless Storefront Down to 101","A headless Shopware 6 + Nuxt storefront loaded 531 requests on its mobile homepage and scored 56 in Lighthouse. After one batch of changes on production it was 101 requests and 88. How I measured, where the weight came from, what I reverted, and a checklist for your own storefront.",{"seoTitle":731,"date":732,"image":733,"imageWidth":496,"imageHeight":497,"alt":734,"tags":735,"author":502,"published":152,"featured":503},"Headless Storefront Performance: 531 to 101 Requests","29.10.2026","/blogs-img/storefront-requests.webp","A storefront waterfall chart shrinking from a dense wall of requests to a short, tidy list, with a performance gauge moving from orange to green",[520,519],{"path":737,"title":738,"description":739,"meta":740},"/blogs/ai-agent-readiness-website","Making Your Website Readable for AI Agents — What Actually Matters","llms.txt, agents.md, ai-catalog.json, AI-bot rules in robots.txt. I shipped all of it on marcofaul.de, then audited it and found four of my own files broken or missing. What the 2026 data says about these files, what really decides whether AI tools can read your site, and a checklist to verify it.",{"seoTitle":741,"date":742,"image":743,"imageWidth":496,"imageHeight":497,"alt":744,"tags":745,"author":502,"published":152,"featured":503},"AI Agent Readiness: llms.txt, AGENTS.md and What Matters","31.10.2026","/blogs-img/agent-readiness.webp","A website feeding server-rendered HTML, structured data and small machine-readable files to AI crawlers, with one broken file highlighted",[573,746],"seo",{"path":748,"title":749,"description":750,"meta":751},"/blogs/headless-gamechanger","Why Headless Shopware 6 with Nuxt is a Game-Changer for Your Online Store","Going headless with Shopware 6 and Nuxt isn't just a tech trend—it's a competitive advantage. Discover why separating your frontend from backend delivers blazing-fast performance, incredible flexibility, and happier customers.",{"seoTitle":752,"date":723,"image":753,"imageWidth":496,"imageHeight":497,"alt":754,"tags":755,"published":152,"featured":152},"Headless Shopware 6 with Nuxt - Why It Wins","/blogs-img/shopware-nuxt-headless.webp","Headless Shopware 6 with Nuxt - The future of e-commerce",[519,531],{"path":757,"title":758,"description":759,"meta":760},"/blogs/quality-tools-that-matter","Code Quality Tools That Actually Matter - Your PR Review Checklist","Stop shipping bugs and messy code. These essential code quality tools catch issues before they hit production, making your team faster and your code cleaner.",{"seoTitle":761,"date":723,"image":762,"imageWidth":496,"imageHeight":497,"alt":763,"tags":764,"published":152},"Code Quality Tools That Actually Matter","/blogs-img/code-quality-tools.webp","Essential code quality tools for modern development",[500,501],{"path":766,"title":767,"description":768,"meta":769},"/blogs/shopware-67-migration-guide","Shopware 6.6 to 6.7 Migration Guide - Breaking Changes and a Safe Upgrade Path","Upgrading Shopware 6.6 to 6.7? Here are the real breaking changes - Vite, Symfony 7.4, Pinia, delayed cache - and a tested upgrade path that won't break production.",{"seoTitle":770,"date":558,"image":771,"imageWidth":496,"imageHeight":497,"alt":772,"tags":773,"author":502,"published":152,"featured":152},"Shopware 6.6 to 6.7 Migration Guide","/blogs-img/shopware-67-migration.webp","Shopware 6.6 to 6.7 migration guide - breaking changes and upgrade path",[519,501],{"path":775,"title":776,"description":777,"meta":778},"/blogs/nuxt-4-migration-guide","Migrating to Nuxt 4 - The New app/ Directory, Smarter Data Fetching, and a Painless Upgrade","Nuxt 4 is here. Learn the new app/ directory structure, improved useFetch/useAsyncData, the path-alias gotcha, and how to upgrade safely with codemods.",{"seoTitle":779,"date":780,"image":781,"imageWidth":496,"imageHeight":497,"alt":782,"tags":783,"author":502,"published":152,"featured":152},"Nuxt 4 Migration Guide","10.06.2026","/blogs-img/nuxt-4-migration.webp","Migrating to Nuxt 4 - new app directory and data fetching",[531,501],{"path":785,"title":786,"description":787,"meta":788},"/blogs/core-web-vitals-inp-2026","Core Web Vitals 2026 - How to Master INP (Interaction to Next Paint)","INP is the Core Web Vital most sites fail. Learn what INP measures, the 200ms threshold, and concrete JavaScript techniques to make your store feel instant.",{"seoTitle":789,"date":790,"image":791,"imageWidth":496,"imageHeight":497,"alt":792,"tags":793,"author":502,"published":152,"featured":503},"Core Web Vitals 2026 - Mastering INP","04.06.2026","/blogs-img/core-web-vitals-inp.webp","Master INP Interaction to Next Paint Core Web Vitals 2026",[520,531],{"path":795,"title":796,"description":797,"meta":798},"/blogs/ai-product-search-shopware","AI-Powered Product Search in Shopware - Semantic and Vector Search That Converts","Keyword search misses what shoppers mean. Here's how to add AI semantic/vector search to Shopware 6 with embeddings - the architecture, the tradeoffs, and a practical build.",{"seoTitle":799,"date":800,"image":801,"imageWidth":496,"imageHeight":497,"alt":802,"tags":803,"author":502,"published":152,"featured":152},"AI Product Search in Shopware","09.06.2026","/blogs-img/ai-product-search.webp","AI-powered semantic and vector product search in Shopware 6",[519,573],1793447960787]