--- title: MEF will not get easier, it’s cool as ICE | daily.dev description: A beginner-friendly explanation of the Managed Extensibility Framework (MEF) for .NET, using a shed-building analogy to illustrate its three core concepts:... canonical: https://daily.dev/posts/mef-will-not-get-easier-it-s-cool-as-ice-f9kqgjsob twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: MEF will not get easier, it’s cool as ICE | daily.dev og:description: A beginner-friendly explanation of the Managed Extensibility Framework (MEF) for .NET, using a shed-building analogy to illustrate its three core concepts:... og:url: https://daily.dev/posts/mef-will-not-get-easier-it-s-cool-as-ice-f9kqgjsob og:image: https://api.daily.dev/og/posts/F9kQGjsOb.png og:image:alt: MEF will not get easier, it’s cool as ICE 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. # MEF will not get easier, it’s cool as ICE **[Maarten Balliauw](https://daily.dev/sources/maartenballiauw)** · 4 min read · 0 upvotes · 0 comments ## Summary A beginner-friendly explanation of the Managed Extensibility Framework (MEF) for .NET, using a shed-building analogy to illustrate its three core concepts: Export, Import, and Compose. The post walks through labeling classes with ExportAttribute, consuming them via ImportAttribute/ImportManyAttribute, and wiring everything together with a CompositionContainer, framing the mnemonic 'ICE' (Import, Compose, Export) to help readers remember the pattern. It also briefly mentions advanced features like metadata-based imports and custom export providers. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What do the Export and Import attributes do in the Managed Extensibility Framework (MEF)? The ExportAttribute marks a type or property as available for MEF to discover and provide to consumers, acting like a label. The ImportAttribute (or ImportManyAttribute for collections) marks where a consuming class wants that exported type injected. A CompositionContainer built from a catalog then calls ComposeParts to match exports to imports and satisfy all required dependencies. _Developers wiring up MEF-based composition can find more dependency injection patterns on daily.dev._ ## Similar posts on daily.dev - [Abstractions That Heal, Abstractions That Harm](https://daily.dev/posts/abstractions-that-heal-abstractions-that-harm-byjb3ozq1) · We Are .NET · 58 upvotes · 3 comments - [Microsoft Agent Framework for .NET \(part 4\): static methods, instance methods, MCP Clients as custom Agent tools](https://daily.dev/posts/microsoft-agent-framework-for-net-part-4-static-methods-instance-methods-mcp-clients-as-custom-ic9gudajq) · Code4IT · 1 upvotes · 0 comments - [Performance improvements to MEF-based editor productivity extensions](https://daily.dev/posts/performance-improvements-to-mef-based-editor-productivity-extensions-wnu5qqkqf) · Visual Studio Blog · 8 upvotes · 1 comments - [Module Federation: The Backbone of Modern Micro-Frontends](https://daily.dev/posts/module-federation-the-backbone-of-modern-micro-frontends-4kpagluxb) · Medium · 3 upvotes · 0 comments --- Tags: [#.net](https://daily.dev/tags/.net), [#c#](https://daily.dev/tags/c#), [#dependency-injection](https://daily.dev/tags/dependency-injection) [View this post on daily.dev](https://daily.dev/posts/mef-will-not-get-easier-it-s-cool-as-ice-f9kqgjsob) ```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":"MEF will not get easier, it’s cool as ICE","url":"https://daily.dev/posts/mef-will-not-get-easier-it-s-cool-as-ice-f9kqgjsob","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/mef-will-not-get-easier-it-s-cool-as-ice-f9kqgjsob"},"datePublished":"2026-10-04T13:05:00.132Z","dateModified":"2026-10-04T13:10:54.991Z","description":"A beginner-friendly explanation of the Managed Extensibility Framework (MEF) for .NET, using a shed-building analogy to illustrate its three core concepts:...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/59000f1ec8527ef30504aa26acc7f62b?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/59000f1ec8527ef30504aa26acc7f62b?_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/mef-will-not-get-easier-it-s-cool-as-ice-f9kqgjsob","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":".net,c#,dependency-injection","timeRequired":"PT4M"} {"@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":"MEF will not get easier, it’s cool as ICE"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/mef-will-not-get-easier-it-s-cool-as-ice-f9kqgjsob#faq","mainEntity":[{"@type":"Question","name":"What do the Export and Import attributes do in the Managed Extensibility Framework (MEF)?","acceptedAnswer":{"@type":"Answer","text":"The ExportAttribute marks a type or property as available for MEF to discover and provide to consumers, acting like a label. 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