--- title: Issue 534 | daily.dev description: Haskell Weekly issue 534 covers enterprise Haskell in production at H-E-B (nearly a million lines over 8 years in supply chain), a new workaround for... canonical: https://daily.dev/posts/issue-534-rpp60utgy twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Issue 534 | daily.dev og:description: Haskell Weekly issue 534 covers enterprise Haskell in production at H-E-B (nearly a million lines over 8 years in supply chain), a new workaround for... og:url: https://daily.dev/posts/issue-534-rpp60utgy og:image: https://api.daily.dev/og/posts/Rpp60UTgy.png og:image:alt: Issue 534 og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Issue 534 **[Haskell Weekly](https://daily.dev/sources/haskellwkly)** · 5 min read · 0 upvotes · 0 comments ## Summary Haskell Weekly issue 534 covers enterprise Haskell in production at H-E-B (nearly a million lines over 8 years in supply chain), a new workaround for existential quantification using a linear proof-token approach, QuickCheck property-based testing introduction, LLM constraint-evading behavior when writing Haskell, a new falsify release (Hypothesis-inspired shrinking library), profunctor optics via Tannakian Reconstruction, and servant-auth roles implementation. Also includes a job posting, new libraries (hgg grammar-of-graphics, servant-auth-role), a static site generator starter using Shake, and community calls for participation. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Issue 526](https://daily.dev/posts/issue-526-62ezskket) · Haskell Weekly · 0 upvotes · 0 comments - [Issue 524](https://daily.dev/posts/issue-524-mrzhkdyws) · Haskell Weekly · 0 upvotes · 0 comments - [Issue 518](https://daily.dev/posts/issue-518-7hhap2wpm) · Haskell Weekly · 0 upvotes · 0 comments - [Issue 514](https://daily.dev/posts/issue-514-3fr4ho1f3) · Haskell Weekly · 0 upvotes · 0 comments - [Issue 522](https://daily.dev/posts/issue-522-3o8bg75xd) · Haskell Weekly · 0 upvotes · 0 comments --- Tags: [#functional-programming](https://daily.dev/tags/functional-programming), [#haskell](https://daily.dev/tags/haskell), [#testing](https://daily.dev/tags/testing), [#type-systems](https://daily.dev/tags/type-systems) [View this post on daily.dev](https://daily.dev/posts/issue-534-rpp60utgy) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Issue 534","url":"https://daily.dev/posts/issue-534-rpp60utgy","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/issue-534-rpp60utgy"},"datePublished":"2026-07-23T09:44:00.935Z","dateModified":"2026-10-14T02:26:39.343Z","description":"Haskell Weekly issue 534 covers enterprise Haskell in production at H-E-B (nearly a million lines over 8 years in supply chain), a new workaround for...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/5587ac300cdc202253958d224e471b4b?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/5587ac300cdc202253958d224e471b4b?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Haskell Weekly","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"Haskell Weekly","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/e30aaf87f5af479cab08b891bb4fcaaa","url":"https://daily.dev/sources/haskellwkly"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/issue-534-rpp60utgy","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"functional-programming,haskell,testing,type-systems","timeRequired":"PT5M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Haskell Weekly","item":"https://daily.dev/sources/haskellwkly"},{"@type":"ListItem","position":3,"name":"Issue 534"}]} ```