managedcode-mimetypes
ManagedCode.MimeTypes is a .NET library that provides centralized MIME type detection and file extension to content-type mapping. Use it when building upload or download flows that require consistent content-type decisions, preventing scattered ad-hoc string tables across services and ensuring reliable HTTP response headers and storage metadata for file handling.
git clone --depth 1 https://github.com/managedcode/dotnet-skills /tmp/managedcode-mimetypes && cp -r /tmp/managedcode-mimetypes/catalog/Libraries/ManagedCode-MimeTypes/skills/managedcode-mimetypes ~/.claude/skills/managedcode-mimetypesSKILL.md
# ManagedCode.MimeTypes ## Trigger On - integrating `ManagedCode.MimeTypes` into upload or download flows - mapping file extensions to content types in APIs or background processing - reviewing content-type handling for files, blobs, or attachments - documenting a reusable MIME-type decision point in a .NET application ## Workflow 1. Identify where the application needs stable MIME-type decisions: - upload validation - download response headers - storage metadata - attachment processing 2. Centralize content-type mapping instead of scattering ad-hoc string tables across the codebase. 3. Use one library boundary for extension and MIME lookups. 4. Validate the extensions and media types that matter to the product. 5. Document any product-specific overrides separately from the library defaults. ```mermaid flowchart LR A["File name or extension"] --> B["ManagedCode.MimeTypes lookup"] B --> C["Resolved MIME type"] C --> D["Upload validation, storage metadata, or HTTP response"] ``` ## Deliver - guidance on where MIME lookup belongs in application code - recommendations for centralized content-type decisions - validation expectations for real file types used by the product ## Validate - MIME mapping is not duplicated across multiple services or controllers - important file types are verified explicitly - response or storage code uses the resolved type consistently
Build, debug, modernize, or review ASP.NET Core applications with correct hosting, middleware, security, configuration, logging, and deployment patterns on current .NET. USE FOR: working on ASP.NET Core apps, services, or middleware; changing auth, routing, configuration, hosting, or deployment behavior; deciding between ASP.NET Core sub-stacks. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
Build, upgrade, and operate .NET Aspire 13.3.x application hosts with current CLI, AppHost, ServiceDefaults, integrations, dashboard, testing, and Azure deployment patterns for distributed apps. USE FOR: Aspire.AppHost.Sdk, Aspire.Hosting.*, DistributedApplication.CreateBuilder, WithReference, WaitFor, AddProject, AddRedis, AddPostgres, aspire run, aspire init, aspire. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
Build, review, or migrate Azure Functions in .NET with correct execution model, isolated worker setup, bindings, DI, and Durable Functions patterns. USE FOR: working on Azure Functions in .NET; migrating from the in-process model to the isolated worker model; adding Durable Functions, bindings, or host configuration. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
Build and review Blazor applications across server, WebAssembly, web app, and hybrid scenarios with correct component design, state flow, rendering, and hosting choices. USE FOR: building interactive web UIs with C# instead of JavaScript; choosing between Server, WebAssembly, or Auto render modes; designing component hierarchies and state. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
Maintain or migrate EF6-based applications with realistic guidance on what to keep, what to modernize, and when EF Core is or is not the right next step. USE FOR: EF6 codebases; runtime versus ORM migration decisions; EDMX, code-first, ObjectContext, and legacy data-access review. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
Design, tune, or review EF Core data access with proper modeling, migrations, query translation, performance, and lifetime management for modern .NET applications. USE FOR: DbContext, migrations, model configuration, EF queries, tracking, loading, performance, transactions, and EF6 migration decisions. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
Build, review, or migrate .NET MAUI applications across Android, iOS, macOS, and Windows with correct cross-platform UI, platform integration, and native packaging assumptions. USE FOR: working on cross-platform mobile or desktop UI in .NET MAUI; integrating device capabilities, navigation, or platform-specific code; migrating Xamarin.Forms or aligning. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
Use ML.NET to train, evaluate, or integrate machine-learning models into .NET applications with realistic data preparation, inference, and deployment expectations. USE FOR: ML.NET integration; local model training or retraining; inference pipelines, model loading, evaluation, and deployment review. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.