--- title: [RFC] Case sensitive PHP | daily.dev description: A PHP internals mailing list thread discussing a proposed RFC to make PHP fully case-sensitive. Currently, PHP treats class names, function names, and other... canonical: https://daily.dev/posts/rfc-case-sensitive-php-npomkgpbs twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: [RFC] Case sensitive PHP | daily.dev og:description: A PHP internals mailing list thread discussing a proposed RFC to make PHP fully case-sensitive. Currently, PHP treats class names, function names, and other... og:url: https://daily.dev/posts/rfc-case-sensitive-php-npomkgpbs og:image: https://api.daily.dev/og/posts/NPOMKGpBS.png og:image:alt: [RFC] Case sensitive PHP 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. # [RFC] Case sensitive PHP **[externals.io](https://daily.dev/sources/externals)** · 7 min read · 0 upvotes · 0 comments ## Summary A PHP internals mailing list thread discussing a proposed RFC to make PHP fully case-sensitive. Currently, PHP treats class names, function names, and other identifiers case-insensitively. The RFC author Jorg Sowa is reviving the discussion and plans to add impact analysis and performance benchmarks. Supporters argue it would simplify static analysis and align PHP with most other languages. Critics raise concerns about PHP's inconsistent built-in naming conventions (DateTime vs PDO vs mysqli) creating confusion once case-sensitivity is enforced, and question whether the benefits justify the migration burden. Technical details discussed include how deprecations would be promoted to errors in PHP 9.0 and the behavior of the ::class constant. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [\[RFC\] Case sensitive PHP](https://daily.dev/posts/rfc-case-sensitive-php-kmec1cfcz) · externals.io · 0 upvotes · 0 comments - [\[RFC\] Case sensitive PHP](https://daily.dev/posts/rfc-case-sensitive-php-qfziw1cvl) · externals.io · 0 upvotes · 0 comments - [\[RFC\] Case sensitive PHP](https://daily.dev/posts/rfc-case-sensitive-php-af7rrnywp) · externals.io · 0 upvotes · 0 comments --- Tags: [#php](https://daily.dev/tags/php), [#language-design](https://daily.dev/tags/language-design) [View this post on daily.dev](https://daily.dev/posts/rfc-case-sensitive-php-npomkgpbs) ```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":"[RFC] Case sensitive PHP","url":"https://daily.dev/posts/rfc-case-sensitive-php-npomkgpbs","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/rfc-case-sensitive-php-npomkgpbs"},"datePublished":"2026-06-17T14:26:22.289Z","dateModified":"2026-06-17T14:49:15.463Z","description":"A PHP internals mailing list thread discussing a proposed RFC to make PHP fully case-sensitive. 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