--- title: Inheritance is evil! | daily.dev description: A short post links to and endorses an argument that object-oriented inheritance ('is-a' relationships) is often a design mistake, and that composition ('has-a'... canonical: https://daily.dev/posts/inheritance-is-evil--jdlgwzhj4 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Inheritance is evil! | daily.dev og:description: A short post links to and endorses an argument that object-oriented inheritance ('is-a' relationships) is often a design mistake, and that composition ('has-a'... og:url: https://daily.dev/posts/inheritance-is-evil--jdlgwzhj4 og:image: https://api.daily.dev/og/posts/jdLGwZHJ4.png og:image:alt: Inheritance is evil! 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. # Inheritance is evil! **[Maarten Balliauw](https://daily.dev/sources/maartenballiauw)** · 1 min read · 0 upvotes · 0 comments ## Summary A short post links to and endorses an argument that object-oriented inheritance ('is-a' relationships) is often a design mistake, and that composition ('has-a' relationships) via patterns like Strategy is usually preferable. The author recommends reading the full linked article for the detailed reasoning. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Why Your Software Sucks: Inheritance](https://daily.dev/posts/why-your-software-sucks-inheritance-pnnmgu4k8) · Aaronontheweb · 28 upvotes · 3 comments - [Design Patterns Suck](https://daily.dev/posts/design-patterns-suck-kei3cx9df) · iamluminousmen · 1 upvotes · 0 comments --- Tags: [#design-patterns](https://daily.dev/tags/design-patterns) [View this post on daily.dev](https://daily.dev/posts/inheritance-is-evil--jdlgwzhj4) ```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":"Inheritance is evil!","url":"https://daily.dev/posts/inheritance-is-evil--jdlgwzhj4","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/inheritance-is-evil--jdlgwzhj4"},"datePublished":"2026-10-04T13:05:06.229Z","dateModified":"2026-10-04T13:10:46.923Z","description":"A short post links to and endorses an argument that object-oriented inheritance ('is-a' relationships) is often a design mistake, and that composition ('has-a'...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/f3fad5621f44c2adf48ebf2c5c6a5e3f?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/f3fad5621f44c2adf48ebf2c5c6a5e3f?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Maarten Balliauw","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":"Maarten Balliauw","logo":"https://media.daily.dev/image/upload/s--rOTg3VYO--/f_auto,q_auto/v1791119043/logos/maartenballiauw?_a=BAMAMicg0","url":"https://daily.dev/sources/maartenballiauw"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/inheritance-is-evil--jdlgwzhj4","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"design-patterns","timeRequired":"PT1M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Maarten Balliauw","item":"https://daily.dev/sources/maartenballiauw"},{"@type":"ListItem","position":3,"name":"Inheritance is evil!"}]} ```