--- title: Implementing strongly-typed IDs in .NET for safer domain... description: Primitive obsession—using int or string for entity IDs—allows IDs to be passed interchangeably, causing logic errors that only surface at runtime.... canonical: https://daily.dev/posts/implementing-strongly-typed-ids-in-net-for-safer-domain-models-hzrg4axc7 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Implementing strongly-typed IDs in .NET for safer domain models | daily.dev og:description: Primitive obsession—using int or string for entity IDs—allows IDs to be passed interchangeably, causing logic errors that only surface at runtime.... og:url: https://daily.dev/posts/implementing-strongly-typed-ids-in-net-for-safer-domain-models-hzrg4axc7 og:image: https://api.daily.dev/og/posts/hzRg4Axc7.png og:image:alt: Implementing strongly-typed IDs in .NET for safer domain models 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. # Implementing strongly-typed IDs in .NET for safer domain models **[elmah.io](https://daily.dev/sources/elmah)** · [@thomasardal](https://daily.dev/thomasardal) · 10 upvotes · 1 comments ## Summary Primitive obsession—using int or string for entity IDs—allows IDs to be passed interchangeably, causing logic errors that only surface at runtime. Strongly-typed IDs solve this by wrapping primitives in readonly record structs, giving each entity its own ID type. EF Core supports this through ValueConverter, which stores the underlying int while enforcing type safety at compile time. This approach catches ID mismatches early, improves method signature clarity, and encapsulates domain meaning without manual validation. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Community discussion Top comments from developers on daily.dev. **@mariuszjamro** · 0 upvotes > Why struct not class? ## Similar posts on daily.dev - [Don’t just attend KubeCon \+ CloudNativeCon, Merge Forward your experience\!](https://daily.dev/posts/don-t-just-attend-kubecon-cloudnativecon-merge-forward-your-experience--l0rpp73x8) · CNCF · 1 upvotes · 0 comments - [Announcing H2 2026 KCDs](https://daily.dev/posts/announcing-h2-2026-kcds-m96goajm1) · CNCF · 1 upvotes · 0 comments - [Two months of Open Community Groups](https://daily.dev/posts/two-months-of-open-community-groups-asf52zhbs) · CNCF · 0 upvotes · 0 comments - [CNCF Unveils Schedule for KubeCon \+ CloudNativeCon Europe 2026](https://daily.dev/posts/cncf-unveils-schedule-for-kubecon-cloudnativecon-europe-2026-ikhcoa5cb) · CNCF · 2 upvotes · 0 comments - [CNCF Debuts KubeCon \+ CloudNativeCon Japan 2026 Schedule](https://daily.dev/posts/cncf-debuts-kubecon-cloudnativecon-japan-2026-schedule-xp5pyudub) · CNCF · 1 upvotes · 0 comments --- Tags: [#.net](https://daily.dev/tags/.net), [#c#](https://daily.dev/tags/c#), [#domain-driven-design](https://daily.dev/tags/domain-driven-design) [View this post on daily.dev](https://daily.dev/posts/implementing-strongly-typed-ids-in-net-for-safer-domain-models-hzrg4axc7) ```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":"DiscussionForumPosting","mainEntityOfPage":"https://daily.dev/posts/implementing-strongly-typed-ids-in-net-for-safer-domain-models-hzrg4axc7","headline":"Implementing strongly-typed IDs in .NET for safer domain models","text":"Shared: Implementing strongly-typed IDs in .NET for safer domain models","url":"https://daily.dev/posts/implementing-strongly-typed-ids-in-net-for-safer-domain-models-hzrg4axc7","datePublished":"2026-02-10T07:47:33.935Z","dateModified":"2026-02-10T07:48:11.894Z","author":{"@type":"Person","name":"Thomas Ardal","url":"https://daily.dev/thomasardal","image":"https://avatars.githubusercontent.com/u/563206?v=4","description":"Hi. I'm Thomas, the founder of elmah.io.","interactionStatistic":{"@type":"InteractionCounter","interactionType":{"@type":"EndorseAction"},"userInteractionCount":280}},"image":"https://media.daily.dev/image/upload/s--OHB84bZF--/f_auto/v1722860399/public/Placeholder%2010","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":10},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":1}],"sharedContent":{"@type":"WebPage","url":"https://api.daily.dev/r/O2ol7WK2t"},"comment":[{"@type":"Comment","text":"Why struct not class?","datePublished":"2026-02-17T10:57:11.489Z","url":"https://daily.dev/posts/hzRg4Axc7#c-L1Nue6yod","author":{"@type":"Person","name":"Mariusz Jamro","url":"https://daily.dev/mariuszjamro","image":"https://lh3.googleusercontent.com/a/ACg8ocI3lHVduDex32D8dPpv9xLodyWVYXOCaoW4S0PqWegLeXsAcCbo=s96-c"}}],"isPartOf":{"@type":"WebPage","url":"https://daily.dev/squads/elmah","name":"elmah.io"}} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"elmah.io","item":"https://daily.dev/squads/elmah"},{"@type":"ListItem","position":3,"name":"Implementing strongly-typed IDs in .NET for safer domain models"}]} ```