--- title: Union types in C# | daily.dev description: C# lacks native union types, but several workarounds exist. Using abstract records with a private constructor simulates discriminated unions and enables... canonical: https://daily.dev/posts/union-types-in-c--jtlxv0quk twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Union types in C# | daily.dev og:description: C# lacks native union types, but several workarounds exist. Using abstract records with a private constructor simulates discriminated unions and enables... og:url: https://daily.dev/posts/union-types-in-c--jtlxv0quk og:image: https://api.daily.dev/og/posts/JTLxv0QuK.png og:image:alt: Union types in C# 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. # Union types in C# **[Event-Driven by Oskar Dudycz](https://daily.dev/sources/event-driven-io)** · 12 min read · 0 upvotes · 0 comments ## Summary C# lacks native union types, but several workarounds exist. Using abstract records with a private constructor simulates discriminated unions and enables pattern matching for domain modeling (e.g., shopping cart states). For simpler cases, tuples with nullable fields can work, though they're verbose. A custom Maybe type and Either class provide cleaner semantics, including Map and Switch methods for exhaustive handling. For three or more types, a OneOf class or the existing OneOf library can be used. The author recommends applying these patterns selectively in domain/business logic code, while cautioning against over-engineering, and advocates for native C# union type support. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Working union types into C\#](https://daily.dev/posts/working-union-types-into-c--n1rhxnbqf) · Atomic Spin · 0 upvotes · 0 comments --- Tags: [#architecture](https://daily.dev/tags/architecture), [#c#](https://daily.dev/tags/c#), [#functional-programming](https://daily.dev/tags/functional-programming) [View this post on daily.dev](https://daily.dev/posts/union-types-in-c--jtlxv0quk) ```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":"Union types in C#","url":"https://daily.dev/posts/union-types-in-c--jtlxv0quk","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/union-types-in-c--jtlxv0quk"},"datePublished":"2026-06-17T11:26:23.933Z","dateModified":"2026-06-17T11:34:25.879Z","description":"C# lacks native union types, but several workarounds exist. 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