[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"skill-dotnet-migrate-dotnet8-to-dotnet9":3,"mdc--xihgi3-key":34,"related-org-dotnet-migrate-dotnet8-to-dotnet9":2671,"related-repo-dotnet-migrate-dotnet8-to-dotnet9":2836},{"slug":4,"name":4,"fn":5,"description":6,"org":7,"tags":11,"stars":22,"repoUrl":23,"updatedAt":24,"license":25,"forks":26,"topics":27,"repo":29,"sourceUrl":32,"mdContent":33},"migrate-dotnet8-to-dotnet9","migrate .NET 8 projects to .NET 9","Migrate a .NET 8 project to .NET 9 and resolve all breaking changes. USE FOR: upgrading TargetFramework from net8.0 to net9.0, fixing build errors after updating the .NET 9 SDK, resolving behavioral changes in .NET 9 \u002F C# 13 \u002F ASP.NET Core 9 \u002F EF Core 9, replacing BinaryFormatter (now always throws), resolving SYSLIB0054-SYSLIB0057, adapting to params span overload resolution, fixing C# 13 compiler changes, updating HttpClientFactory for SocketsHttpHandler, and resolving EF Core 9 migration\u002FCosmos DB changes. DO NOT USE FOR: .NET Framework migrations, upgrading from .NET 7 or earlier, greenfield .NET 9 projects, or cosmetic modernization unrelated to the upgrade.\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},"dotnet",".NET (Microsoft)","https:\u002F\u002Fpexgzepcugksgbtrxkhf.supabase.co\u002Fstorage\u002Fv1\u002Fobject\u002Fpublic\u002Forg-logos\u002Fdotnet.png",[12,16,19],{"name":13,"slug":14,"type":15},".NET","net","tag",{"name":17,"slug":18,"type":15},"Migration","migration",{"name":20,"slug":21,"type":15},"Engineering","engineering",4576,"https:\u002F\u002Fgithub.com\u002Fdotnet\u002Fskills","2026-07-12T08:23:00.31847","MIT",332,[28],"agent-skills",{"repoUrl":23,"stars":22,"forks":26,"topics":30,"description":31},[28],"Repository for skills to assist AI coding agents with .NET and C#","https:\u002F\u002Fgithub.com\u002Fdotnet\u002Fskills\u002Ftree\u002FHEAD\u002Fplugins\u002Fdotnet-upgrade\u002Fskills\u002Fmigrate-dotnet8-to-dotnet9","---\nname: migrate-dotnet8-to-dotnet9\ndescription: >\n  Migrate a .NET 8 project to .NET 9 and resolve all breaking changes.\n  USE FOR: upgrading TargetFramework from net8.0 to net9.0, fixing build errors\n  after updating the .NET 9 SDK, resolving behavioral changes in .NET 9 \u002F C# 13 \u002F\n  ASP.NET Core 9 \u002F EF Core 9, replacing BinaryFormatter (now always throws),\n  resolving SYSLIB0054-SYSLIB0057, adapting to params span overload resolution,\n  fixing C# 13 compiler changes, updating HttpClientFactory for SocketsHttpHandler,\n  and resolving EF Core 9 migration\u002FCosmos DB changes.\n  DO NOT USE FOR: .NET Framework migrations, upgrading from .NET 7 or earlier,\n  greenfield .NET 9 projects, or cosmetic modernization unrelated to the upgrade.\nlicense: MIT\n---\n\n# .NET 8 → .NET 9 Migration\n\nMigrate a .NET 8 project or solution to .NET 9, systematically resolving all breaking changes. The outcome is a project targeting `net9.0` that builds cleanly, passes tests, and accounts for every behavioral, source-incompatible, and binary-incompatible change introduced in the .NET 9 release.\n\n## When to Use\n\n- Upgrading `TargetFramework` from `net8.0` to `net9.0`\n- Resolving build errors or new warnings after updating the .NET 9 SDK\n- Adapting to behavioral changes in .NET 9 runtime, ASP.NET Core 9, or EF Core 9\n- Replacing `BinaryFormatter` usage (now always throws at runtime)\n- Updating CI\u002FCD pipelines, Dockerfiles, or deployment scripts for .NET 9\n\n## When Not to Use\n\n- The project already targets `net9.0` and builds cleanly — migration is done. If the goal is to reach `net10.0`, use the `migrate-dotnet9-to-dotnet10` skill as the next step.\n- Upgrading from .NET 7 or earlier — address the prior version breaking changes first\n- Migrating from .NET Framework — that is a separate, larger effort\n- Greenfield projects that start on .NET 9 (no migration needed)\n\n## Inputs\n\n| Input | Required | Description |\n|-------|----------|-------------|\n| Project or solution path | Yes | The `.csproj`, `.sln`, or `.slnx` entry point to migrate |\n| Build command | No | How to build (e.g., `dotnet build`, a repo build script). Auto-detect if not provided |\n| Test command | No | How to run tests (e.g., `dotnet test`). Auto-detect if not provided |\n| Project type hints | No | Whether the project uses ASP.NET Core, EF Core, WinForms, WPF, containers, etc. Auto-detect from PackageReferences and SDK attributes if not provided |\n\n## Workflow\n\n> **Answer directly from the loaded reference documents.** Do not search the filesystem or fetch web pages for breaking change information — the references contain the authoritative details. Focus on identifying which breaking changes apply and providing concrete fixes.\n>\n> **Commit strategy:** Commit at each logical boundary — after updating the TFM (Step 2), after resolving build errors (Step 3), after addressing behavioral changes (Step 4), and after updating infrastructure (Step 5). This keeps each commit focused and reviewable.\n\n### Step 1: Assess the project\n\n1. Identify how the project is built and tested. Look for build scripts, `.sln`\u002F`.slnx` files, or individual `.csproj` files.\n2. Run `dotnet --version` to confirm the .NET 9 SDK is installed. If it is not, stop and inform the user.\n3. Determine which technology areas the project uses by examining:\n   - **SDK attribute**: `Microsoft.NET.Sdk.Web` → ASP.NET Core; `Microsoft.NET.Sdk.WindowsDesktop` with `\u003CUseWPF>` or `\u003CUseWindowsForms>` → WPF\u002FWinForms\n   - **PackageReferences**: `Microsoft.EntityFrameworkCore.*` → EF Core; `Microsoft.Extensions.Http` → HttpClientFactory\n   - **Dockerfile presence** → Container changes relevant\n   - **P\u002FInvoke or native interop usage** → Interop changes relevant\n   - **`BinaryFormatter` usage** → Serialization migration needed\n   - **`System.Text.Json` usage** → Serialization changes relevant\n   - **X509Certificate constructors** → Cryptography changes relevant\n4. Record which reference documents are relevant (see the reference loading table in Step 3).\n5. Do a **clean build** (`dotnet build --no-incremental` or delete `bin`\u002F`obj`) on the current `net8.0` target to establish a clean baseline. Record any pre-existing warnings.\n\n### Step 2: Update the Target Framework\n\n1. In each `.csproj` (or `Directory.Build.props` if centralized), change:\n   ```xml\n   \u003CTargetFramework>net8.0\u003C\u002FTargetFramework>\n   ```\n   to:\n   ```xml\n   \u003CTargetFramework>net9.0\u003C\u002FTargetFramework>\n   ```\n   For multi-targeted projects, add `net9.0` to `\u003CTargetFrameworks>` or replace `net8.0`.\n\n2. Update all `Microsoft.Extensions.*`, `Microsoft.AspNetCore.*`, `Microsoft.EntityFrameworkCore.*`, and other Microsoft package references to their 9.0.x versions. If using Central Package Management (`Directory.Packages.props`), update versions there.\n\n3. Run `dotnet restore`. Watch for:\n   - **Version requirements**: .NET 9 SDK requires Visual Studio 17.12+ to target `net9.0` (17.11 for `net8.0` and earlier).\n   - **New warnings for .NET Standard 1.x** and **.NET 7 targets** — consider updating or removing outdated target frameworks.\n\n4. Run a clean build. Collect all errors and new warnings. These will be addressed in Step 3.\n\n### Step 3: Resolve build errors and source-incompatible changes\n\nWork through compilation errors and new warnings systematically. Load the appropriate reference documents based on the project type:\n\n| If the project uses… | Load reference |\n|-----------------------|----------------|\n| Any .NET 9 project | `references\u002Fcsharp-compiler-dotnet8to9.md` |\n| Any .NET 9 project | `references\u002Fcore-libraries-dotnet8to9.md` |\n| Any .NET 9 project | `references\u002Fsdk-msbuild-dotnet8to9.md` |\n| ASP.NET Core | `references\u002Faspnet-core-dotnet8to9.md` |\n| Entity Framework Core | `references\u002Fefcore-dotnet8to9.md` |\n| Cryptography APIs | `references\u002Fcryptography-dotnet8to9.md` |\n| System.Text.Json, HttpClient, networking | `references\u002Fserialization-networking-dotnet8to9.md` |\n| Windows Forms or WPF | `references\u002Fwinforms-wpf-dotnet8to9.md` |\n| Docker containers, native interop | `references\u002Fcontainers-interop-dotnet8to9.md` |\n| Runtime configuration, deployment | `references\u002Fdeployment-runtime-dotnet8to9.md` |\n\n**Common source-incompatible changes to check for:**\n\n1. **`params` span overload resolution** — New `params ReadOnlySpan\u003CT>` overloads on `String.Join`, `String.Concat`, `Path.Combine`, `Task.WhenAll`, and many more now bind preferentially. Code calling these methods inside `Expression` lambdas will fail (CS8640\u002FCS9226). See `references\u002Fcore-libraries-dotnet8to9.md`.\n\n2. **`StringValues` ambiguous overload** — The `params Span\u003CT>` feature creates ambiguity with `StringValues` implicit operators on methods like `String.Concat`, `String.Join`, `Path.Combine`. Fix by explicitly casting arguments. See `references\u002Fcore-libraries-dotnet8to9.md`.\n\n3. **New obsoletion warnings (SYSLIB0054–SYSLIB0057)**:\n   - `SYSLIB0054`: Replace `Thread.VolatileRead`\u002F`VolatileWrite` with `Volatile.Read`\u002F`Volatile.Write`\n   - `SYSLIB0057`: Replace `X509Certificate2`\u002F`X509Certificate` binary\u002Ffile constructors with `X509CertificateLoader` methods\n   - Also `SYSLIB0055` (ARM AdvSimd signed overloads) and `SYSLIB0056` (Assembly.LoadFrom with hash algorithm) — see `references\u002Fcore-libraries-dotnet8to9.md`\n\n4. **C# 13 `InlineArray` on record structs** — `[InlineArray]` attribute on `record struct` types is now disallowed (CS9259). Change to a regular `struct`. See `references\u002Fcsharp-compiler-dotnet8to9.md`.\n\n5. **C# 13 iterator safe context** — Iterators now introduce a safe context in C# 13. Local functions inside iterators that used unsafe code inherited from an outer `unsafe` class will now error. Add `unsafe` modifier to the local function. See `references\u002Fcsharp-compiler-dotnet8to9.md`.\n\n6. **C# 13 collection expression overload resolution** — Empty collection expressions (`[]`) no longer use span vs non-span to tiebreak overloads. Exact element type is now preferred. See `references\u002Fcsharp-compiler-dotnet8to9.md`.\n\n7. **`String.Trim(params ReadOnlySpan\u003Cchar>)` removed** — Code compiled against .NET 9 previews that passes `ReadOnlySpan\u003Cchar>` to `Trim`\u002F`TrimStart`\u002F`TrimEnd` must rebuild; the overload was removed in GA. See `references\u002Fcore-libraries-dotnet8to9.md`.\n\n8. **`BinaryFormatter` always throws** — If the project uses `BinaryFormatter`, **stop and inform the user** — this is a major decision. See `references\u002Fserialization-networking-dotnet8to9.md`.\n\n9. **`HttpListenerRequest.UserAgent` is nullable** — The property is now `string?`. Add null checks. See `references\u002Fserialization-networking-dotnet8to9.md`.\n\n10. **Windows Forms nullability annotation changes** — Some WinForms API parameters changed from nullable to non-nullable. Update call sites. See `references\u002Fwinforms-wpf-dotnet8to9.md`.\n\n11. **Windows Forms security analyzers (WFO1000)** — New analyzers produce errors for properties without explicit serialization configuration. See `references\u002Fwinforms-wpf-dotnet8to9.md`.\n\nBuild again after each batch of fixes. Repeat until the build is clean.\n\n### Step 4: Address behavioral changes\n\nBehavioral changes do not cause build errors but may change runtime behavior. Review each applicable item and determine whether the previous behavior was relied upon.\n\n**High-impact behavioral changes (check first):**\n\n1. **Floating-point to integer conversions are now saturating** — Conversions from `float`\u002F`double` to integer types now saturate instead of wrapping on x86\u002Fx64. See `references\u002Fdeployment-runtime-dotnet8to9.md`.\n\n2. **EF Core: Pending model changes exception** — `Migrate()`\u002F`MigrateAsync()` now throws if the model has pending changes. **Search for `DateTime.Now`, `DateTime.UtcNow`, or `Guid.NewGuid()` in any `HasData` call — these must be replaced with fixed constants** (e.g., `new DateTime(2024, 1, 1, 0, 0, 0, DateTimeKind.Utc)`). See `references\u002Fefcore-dotnet8to9.md`.\n\n3. **EF Core: Explicit transaction exception** — `Migrate()` inside a user transaction now throws. See `references\u002Fefcore-dotnet8to9.md`.\n\n4. **HttpClientFactory uses `SocketsHttpHandler` by default** — Code that casts the primary handler to `HttpClientHandler` will get `InvalidCastException`. See `references\u002Fserialization-networking-dotnet8to9.md`.\n\n5. **HttpClientFactory header redaction by default** — All header values in `Trace`-level logs are now redacted. See `references\u002Fserialization-networking-dotnet8to9.md`.\n\n6. **Environment variables take precedence over runtimeconfig.json** — Runtime configuration settings from environment variables now override `runtimeconfig.json`. See `references\u002Fdeployment-runtime-dotnet8to9.md`.\n\n7. **ASP.NET Core `ValidateOnBuild`\u002F`ValidateScopes` in development** — `HostBuilder` now enables DI validation in development by default. See `references\u002Faspnet-core-dotnet8to9.md`.\n\n**Other behavioral changes to review (may cause runtime exceptions ⚠️ or subtle behavioral differences):**\n\n- ⚠️ `FromKeyedServicesAttribute` no longer injects non-keyed service fallback — throws `InvalidOperationException`\n- ⚠️ Container images no longer install zlib — apps depending on system zlib will fail\n- ⚠️ Intel CET is now enabled by default — non-CET-compatible native libraries may cause process termination\n- `BigInteger` now has a maximum length of `(2^31) - 1` bits\n- `JsonDocument` deserialization of JSON `null` now returns non-null `JsonDocument` with `JsonValueKind.Null` instead of C# `null`\n- `System.Text.Json` metadata reader now unescapes metadata property names\n- `ZipArchiveEntry` names\u002Fcomments now respect the UTF-8 flag\n- `IncrementingPollingCounter` initial callback is now asynchronous\n- `InMemoryDirectoryInfo` prepends rootDir to files\n- `RuntimeHelpers.GetSubArray` returns a different type\n- `PictureBox` raises `HttpRequestException` instead of `WebException`\n- `StatusStrip` uses a different default renderer\n- `IMsoComponent` support is opt-in\n- `SafeEvpPKeyHandle.DuplicateHandle` up-refs the handle\n- `HttpClient` metrics report `server.port` unconditionally\n- URI query strings redacted in HttpClient EventSource events and IHttpClientFactory logs\n- `dotnet watch` is incompatible with Hot Reload for old frameworks\n- WPF `GetXmlNamespaceMaps` returns `Hashtable` instead of `String`\n\n### Step 5: Update infrastructure\n\n1. **Dockerfiles**: Update base images. Note that .NET 9 container images no longer install zlib. If your app depends on zlib, add `RUN apt-get update && apt-get install -y zlib1g` to your Dockerfile.\n   ```dockerfile\n   # Before\n   FROM mcr.microsoft.com\u002Fdotnet\u002Fsdk:8.0 AS build\n   FROM mcr.microsoft.com\u002Fdotnet\u002Faspnet:8.0\n   # After\n   FROM mcr.microsoft.com\u002Fdotnet\u002Fsdk:9.0 AS build\n   FROM mcr.microsoft.com\u002Fdotnet\u002Faspnet:9.0\n   ```\n\n2. **CI\u002FCD pipelines**: Update SDK version references. If using `global.json`, update:\n   ```json\n   {\n     \"sdk\": {\n       \"version\": \"9.0.100\",\n       \"rollForward\": \"latestFeature\"\n     }\n   }\n   ```\n   Review the `rollForward` policy — if set to `\"disable\"` or `\"latestPatch\"`, the SDK may not resolve correctly after upgrading. `\"latestFeature\"` (recommended) allows the SDK to roll forward to the latest 9.0.x feature band.\n\n3. **Visual Studio version**: .NET 9 SDK requires VS 17.12+ to target `net9.0`. VS 17.11 can only target `net8.0` and earlier.\n\n4. **Terminal Logger**: `dotnet build` now uses Terminal Logger by default in interactive terminals. CI scripts that parse MSBuild console output may need `--tl:off` or `MSBUILDTERMINALLOGGER=off`.\n\n5. **`dotnet workload` output**: Output format has changed. Update any scripts that parse workload command output.\n\n6. **.NET Monitor images**: Tags simplified to version-only (affects container orchestration referencing specific tags).\n\n### Step 6: Verify\n\n1. Run a full clean build: `dotnet build --no-incremental`\n2. Run all tests: `dotnet test`\n3. If the application is containerized, build and test the container image\n4. Smoke-test the application, paying special attention to:\n   - BinaryFormatter usage (will throw at runtime)\n   - Floating-point to integer conversion behavior\n   - EF Core migration application\n   - HttpClientFactory handler casting and logging\n   - DI validation in development environment\n   - Runtime configuration settings (environment variable precedence)\n5. Review the diff and ensure no unintended behavioral changes were introduced\n\n## Reference Documents\n\nThe `references\u002F` folder contains detailed breaking change information organized by technology area. 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Use this when converting tasks to thread-safe versions, implementing IMultiThreadableTask, adding TaskEnvironment support, or auditing migrations for behavioral compatibility.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2679,2680,2681],{"name":13,"slug":14,"type":15},{"name":20,"slug":21,"type":15},{"name":2682,"slug":2683,"type":15},"Performance","performance",5535,"https:\u002F\u002Fgithub.com\u002Fdotnet\u002Fmsbuild","2026-07-22T05:37:33.965588",{"slug":2688,"name":2688,"fn":2689,"description":2690,"org":2691,"tags":2692,"stars":22,"repoUrl":23,"updatedAt":2701},"analyzing-dotnet-performance","analyze .NET code for performance anti-patterns","Scans .NET code for ~50 performance anti-patterns across async, memory, strings, collections, LINQ, regex, serialization, and I\u002FO with tiered severity classification. Use when analyzing .NET code for optimization opportunities, reviewing hot paths, or auditing allocation-heavy patterns.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2693,2694,2697,2700],{"name":13,"slug":14,"type":15},{"name":2695,"slug":2696,"type":15},"Code Analysis","code-analysis",{"name":2698,"slug":2699,"type":15},"Debugging","debugging",{"name":2682,"slug":2683,"type":15},"2026-07-12T08:23:25.400375",{"slug":2703,"name":2703,"fn":2704,"description":2705,"org":2706,"tags":2707,"stars":22,"repoUrl":23,"updatedAt":2716},"android-tombstone-symbolication","symbolicate .NET runtime frames in Android tombstones","Symbolicate the .NET runtime frames in an Android tombstone file. Extracts BuildIds and PC offsets from the native backtrace, downloads debug symbols from the Microsoft symbol server, and runs llvm-symbolizer to produce function names with source file and line numbers. USE FOR triaging a .NET MAUI or Mono Android app crash from a tombstone, resolving native backtrace frames in libmonosgen-2.0.so or libcoreclr.so to .NET runtime source code, or investigating SIGABRT, SIGSEGV, or other native signals originating from the .NET runtime on Android. DO NOT USE FOR pure Java\u002FKotlin crashes, managed .NET exceptions that are already captured in logcat, or iOS crash logs. INVOKES Symbolicate-Tombstone.ps1 script, llvm-symbolizer, Microsoft symbol server.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2708,2709,2712,2713],{"name":13,"slug":14,"type":15},{"name":2710,"slug":2711,"type":15},"Android","android",{"name":2698,"slug":2699,"type":15},{"name":2714,"slug":2715,"type":15},"Microsoft","microsoft","2026-07-12T08:23:21.595572",{"slug":2718,"name":2718,"fn":2719,"description":2720,"org":2721,"tags":2722,"stars":22,"repoUrl":23,"updatedAt":2734},"apple-crash-symbolication","symbolicate .NET runtime frames in crash logs","Symbolicate .NET runtime frames in Apple platform .ips crash logs (iOS, tvOS, Mac Catalyst, macOS). Extracts UUIDs and addresses from the native backtrace, locates dSYM debug symbols, and runs atos to produce function names with source file and line numbers. Automatically downloads .dwarf symbols from the Microsoft symbol server using Mach-O UUIDs. USE FOR triaging a .NET MAUI or Mono app crash from an .ips file on any Apple platform, resolving native backtrace frames in libcoreclr or libmonosgen-2.0 to .NET runtime source code, retrieving .ips crash logs from a connected iOS device or iPhone, or investigating EXC_CRASH, EXC_BAD_ACCESS, SIGABRT, or SIGSEGV originating from the .NET runtime. DO NOT USE FOR pure Swift\u002FObjective-C crashes with no .NET components, or Android tombstone files. INVOKES Symbolicate-Crash.ps1 script, atos, dwarfdump, idevicecrashreport.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2723,2724,2725,2728,2731],{"name":13,"slug":14,"type":15},{"name":2698,"slug":2699,"type":15},{"name":2726,"slug":2727,"type":15},"iOS","ios",{"name":2729,"slug":2730,"type":15},"macOS","macos",{"name":2732,"slug":2733,"type":15},"Observability","observability","2026-07-12T08:23:20.369986",{"slug":2736,"name":2736,"fn":2737,"description":2738,"org":2739,"tags":2740,"stars":22,"repoUrl":23,"updatedAt":2748},"assertion-quality","evaluate assertion quality in test suites","Analyzes the variety and depth of assertions across test suites in any language. Use when the user asks to evaluate assertion quality, find shallow tests, identify assertion-free tests (no assertions or only trivial ones like Assert.IsNotNull \u002F toBeTruthy()), flag self-referential or tautological assertions, measure assertion diversity, or audit whether tests verify different facets of behavior. Polyglot: .NET, Python, TS\u002FJS, Java, Go, Ruby, Rust, Swift, Kotlin, PowerShell, C++. DO NOT USE FOR: writing new tests (use code-testing-agent \u002F writing-mstest-tests), mutation reasoning about whether tests would catch a bug (use test-gap-analysis), or a general severity-ranked anti-pattern audit (use test-anti-patterns), fixing or rewriting assertions, or writing, fixing, or modernizing MSTest tests, assertions, or attributes (use writing-mstest-tests).",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2741,2742,2745],{"name":2695,"slug":2696,"type":15},{"name":2743,"slug":2744,"type":15},"QA","qa",{"name":2746,"slug":2747,"type":15},"Testing","testing","2026-07-12T08:23:51.277743",{"slug":2750,"name":2750,"fn":2751,"description":2752,"org":2753,"tags":2754,"stars":22,"repoUrl":23,"updatedAt":2768},"author-component","create and review Blazor components","Create or review Blazor components (.razor files) with correct architecture. USE FOR: writing new Blazor components that do NOT involve JavaScript interop, implementing parameters and EventCallback, RenderFragment slots, component lifecycle (OnInitializedAsync, OnParametersSet), async patterns, IAsyncDisposable, CancellationToken, CSS isolation, code-behind. DO NOT USE FOR: creating new projects (use create-blazor-project), JavaScript interop or calling browser APIs from Blazor (use use-js-interop), forms and validation (use collect-user-input), prerendering issues (use support-prerendering), HTTP data fetching patterns (use fetch-and-send-data), coordinating state between unrelated components (use coordinate-components).\n",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2755,2756,2759,2762,2765],{"name":13,"slug":14,"type":15},{"name":2757,"slug":2758,"type":15},"Blazor","blazor",{"name":2760,"slug":2761,"type":15},"C#","csharp",{"name":2763,"slug":2764,"type":15},"UI Components","ui-components",{"name":2766,"slug":2767,"type":15},"Web Development","web-development","2026-07-15T06:03:29.216359",{"slug":2770,"name":2770,"fn":2771,"description":2772,"org":2773,"tags":2774,"stars":22,"repoUrl":23,"updatedAt":2778},"binlog-failure-analysis","analyze MSBuild binary logs","Analyze MSBuild binary logs to diagnose build failures. USE FOR: build errors that are unclear from console output, diagnosing cascading failures across multi-project builds, tracing MSBuild target execution order, and generally any MSBuild build issues. Requires an existing .binlog file. DO NOT USE FOR: generating binlogs (use binlog-generation), non-MSBuild build systems.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2775,2776,2777],{"name":2695,"slug":2696,"type":15},{"name":2698,"slug":2699,"type":15},{"name":2714,"slug":2715,"type":15},"2026-07-12T08:21:34.637923",{"slug":2780,"name":2780,"fn":2781,"description":2782,"org":2783,"tags":2784,"stars":22,"repoUrl":23,"updatedAt":2790},"binlog-generation","generate MSBuild binary logs for diagnostics","Generate MSBuild binary logs (binlogs) for build diagnostics and analysis. USE FOR: adding \u002Fbl:{} to any dotnet build, test, pack, publish, or restore command to capture a full build execution trace, prerequisite for binlog-failure-analysis and build-perf-diagnostics skills, enabling post-build investigation of errors or performance. Requires MSBuild 17.8+ \u002F .NET 8 SDK+ for {} placeholder; PowerShell needs -bl:{{}}. DO NOT USE FOR: non-MSBuild build systems (npm, Maven, CMake), analyzing an existing binlog (use binlog-failure-analysis instead).",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2785,2788,2789],{"name":2786,"slug":2787,"type":15},"Build","build",{"name":2698,"slug":2699,"type":15},{"name":20,"slug":21,"type":15},"2026-07-19T05:38:19.340791",{"slug":2792,"name":2792,"fn":2793,"description":2794,"org":2795,"tags":2796,"stars":22,"repoUrl":23,"updatedAt":2800},"build-parallelism","optimize MSBuild build parallelism","Diagnose and fix under-parallelized MSBuild builds. USE WHEN a multi-project solution build is slower than expected, doesn't speed up when you add cores, pegs a single core while others idle, or you want to know why `-m` isn't helping. Note: `\u002Fmaxcpucount` default is 1 (sequential) — always pass `-m` for parallel builds. Covers finding the critical path (longest serial ProjectReference chain), graph build (`\u002Fgraph`), BuildInParallel, and solution filters (`.slnf`). DO NOT USE FOR: single-project builds, incremental issues (use incremental-build), compilation slowness inside one project (use build-perf-diagnostics), non-MSBuild build systems.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2797,2798,2799],{"name":13,"slug":14,"type":15},{"name":20,"slug":21,"type":15},{"name":2682,"slug":2683,"type":15},"2026-07-19T05:38:18.364937",{"slug":2802,"name":2802,"fn":2803,"description":2804,"org":2805,"tags":2806,"stars":22,"repoUrl":23,"updatedAt":2813},"build-perf-baseline","establish and optimize build performance baselines","Establish build performance baselines and apply systematic optimization techniques. USE FOR: diagnosing slow builds, establishing before\u002Fafter measurements (cold, warm, no-op scenarios), applying optimization strategies like MSBuild Server, static graph builds, artifacts output, and dependency graph trimming. Start here before diving into build-perf-diagnostics, incremental-build, or build-parallelism. DO NOT USE FOR: non-MSBuild build systems, detailed bottleneck analysis (use build-perf-diagnostics after baselining).",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2807,2808,2811,2812],{"name":20,"slug":21,"type":15},{"name":2809,"slug":2810,"type":15},"Monitoring","monitoring",{"name":2682,"slug":2683,"type":15},{"name":2746,"slug":2747,"type":15},"2026-07-12T08:21:35.865649",{"slug":2815,"name":2815,"fn":2816,"description":2817,"org":2818,"tags":2819,"stars":22,"repoUrl":23,"updatedAt":2824},"build-perf-diagnostics","diagnose MSBuild build performance bottlenecks","Diagnose MSBuild build performance bottlenecks using binary log analysis. USE FOR: identifying why builds are slow by analyzing binlog performance summaries, detecting ResolveAssemblyReference (RAR) taking >5s, Roslyn analyzers consuming >30% of Csc time, single targets dominating >50% of build time, node utilization below 80%, excessive Copy tasks, NuGet restore running every build. Covers timeline analysis, Target\u002FTask Performance Summary interpretation, and 7 common bottleneck categories. Use after build-perf-baseline has established measurements. DO NOT USE FOR: establishing initial baselines (use build-perf-baseline first), fixing incremental build issues (use incremental-build), parallelism tuning (use build-parallelism), non-MSBuild build systems.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2820,2821,2822,2823],{"name":13,"slug":14,"type":15},{"name":2698,"slug":2699,"type":15},{"name":20,"slug":21,"type":15},{"name":2682,"slug":2683,"type":15},"2026-07-12T08:21:40.961722",{"slug":2826,"name":2826,"fn":2827,"description":2828,"org":2829,"tags":2830,"stars":22,"repoUrl":23,"updatedAt":2834},"check-bin-obj-clash","detect MSBuild output path conflicts","Detects MSBuild projects with conflicting OutputPath or IntermediateOutputPath. USE FOR: builds failing with 'Cannot create a file when that file already exists', 'The process cannot access the file because it is being used by another process', intermittent build failures that succeed on retry, or missing\u002Foverwritten outputs in multi-project or multi-targeting builds where bin\u002Fobj (or project.assets.json) collide. Common causes: shared OutputPath, missing AppendTargetFrameworkToOutputPath, extra global properties (e.g. PublishReadyToRun), or SetTargetFramework on a ProjectReference to a single-targeting project. DO NOT USE FOR: file access errors unrelated to MSBuild (OS-level locking), single-project single-TFM builds, non-MSBuild build systems.",{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2831,2832,2833],{"name":2698,"slug":2699,"type":15},{"name":20,"slug":21,"type":15},{"name":2743,"slug":2744,"type":15},"2026-07-19T05:38:14.336279",144,{"items":2837,"total":2886},[2838,2845,2852,2860,2866,2874,2880],{"slug":2688,"name":2688,"fn":2689,"description":2690,"org":2839,"tags":2840,"stars":22,"repoUrl":23,"updatedAt":2701},{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2841,2842,2843,2844],{"name":13,"slug":14,"type":15},{"name":2695,"slug":2696,"type":15},{"name":2698,"slug":2699,"type":15},{"name":2682,"slug":2683,"type":15},{"slug":2703,"name":2703,"fn":2704,"description":2705,"org":2846,"tags":2847,"stars":22,"repoUrl":23,"updatedAt":2716},{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2848,2849,2850,2851],{"name":13,"slug":14,"type":15},{"name":2710,"slug":2711,"type":15},{"name":2698,"slug":2699,"type":15},{"name":2714,"slug":2715,"type":15},{"slug":2718,"name":2718,"fn":2719,"description":2720,"org":2853,"tags":2854,"stars":22,"repoUrl":23,"updatedAt":2734},{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2855,2856,2857,2858,2859],{"name":13,"slug":14,"type":15},{"name":2698,"slug":2699,"type":15},{"name":2726,"slug":2727,"type":15},{"name":2729,"slug":2730,"type":15},{"name":2732,"slug":2733,"type":15},{"slug":2736,"name":2736,"fn":2737,"description":2738,"org":2861,"tags":2862,"stars":22,"repoUrl":23,"updatedAt":2748},{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2863,2864,2865],{"name":2695,"slug":2696,"type":15},{"name":2743,"slug":2744,"type":15},{"name":2746,"slug":2747,"type":15},{"slug":2750,"name":2750,"fn":2751,"description":2752,"org":2867,"tags":2868,"stars":22,"repoUrl":23,"updatedAt":2768},{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2869,2870,2871,2872,2873],{"name":13,"slug":14,"type":15},{"name":2757,"slug":2758,"type":15},{"name":2760,"slug":2761,"type":15},{"name":2763,"slug":2764,"type":15},{"name":2766,"slug":2767,"type":15},{"slug":2770,"name":2770,"fn":2771,"description":2772,"org":2875,"tags":2876,"stars":22,"repoUrl":23,"updatedAt":2778},{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2877,2878,2879],{"name":2695,"slug":2696,"type":15},{"name":2698,"slug":2699,"type":15},{"name":2714,"slug":2715,"type":15},{"slug":2780,"name":2780,"fn":2781,"description":2782,"org":2881,"tags":2882,"stars":22,"repoUrl":23,"updatedAt":2790},{"slug":8,"name":9,"logoUrl":10,"githubOrg":8},[2883,2884,2885],{"name":2786,"slug":2787,"type":15},{"name":2698,"slug":2699,"type":15},{"name":20,"slug":21,"type":15},96]